Release notes/1.12

Security reminder
Security reminder: MediaWiki does not require PHP's register_globals setting since version 1.2.0. If you have it on, turn it off if you can.

MediaWiki 1.12.4
February 7, 2009

A number of cross-site scripting (XSS) security vulnerabilities were discovered in the web-based installer (config/index.php). These vulnerabilities all require a live installer -- once the installer has been used to install a wiki, it is deactivated.

Note that cross-site scripting vulnerabilities can be used to attack any website in the same cookie domain. So if you have an uninstalled copy of MediaWiki on the same site as an active web service, MediaWiki could be used to attack the active service.

If you are hosting an old copy of MediaWiki that you have never installed, you are advised to remove it from the web.

MediaWiki 1.12.3

 * Fixed packaging/distribution error. Many files were missing from the distributed tarball.

MediaWiki 1.12.2
David Remahl of Apple's Product Security team has identified a number of security issues in previous releases of MediaWiki. Subsequent analysis by the MediaWiki development team expanded the scope of these vulnerabilities. The issues with a significant impact are as follows:


 * A local script injection vulnerability affecting Internet Explorer clients for all MediaWiki installations with uploads enabled. []
 * A local script injection vulnerability affecting clients with SVG scripting capability (such as Firefox 1.5+), for all MediaWiki installations with SVG uploads enabled. []
 * A CSRF vulnerability affecting the Special:Import feature, for all MediaWiki installations since the feature was introduced in 1.3.0. []

A local script injection vulnerability allows an attacker with a wiki account to steal another user's login session, and to act as that user on the wiki. The attacker uploads a malicious script file, and tricks the victim into executing it.

CSRF vulnerabilities allow an attacker to act as an authorised user on the wiki, but unlike an XSS vulnerability, the attacker can only act as the user in a specific and restricted way. The present CSRF vulnerability allows pages to be edited, with forged revision histories. Like an XSS vulnerability, the authorised user must visit the malicious web page to activate the attack.

These three vulnerabilities are all fixed in this release.

David Remahl also reminded us of some security-related configuration issues:


 * By default, MediaWiki stores a backup of deleted images in the images/deleted directory. If you do not want these images to be publically accessible, make sure this directory is not accessible from the web. MediaWiki takes some steps to avoid leaking these images, but these measures are not perfect.
 * Set display_errors=off in your php.ini to avoid path disclosure via PHP fatal errors. This is the default on most shared web hosts.
 * Enabling MediaWiki's debugging features, such as $wgShowExceptionDetails, may lead to path disclosure.

Other changes in this release:


 * Avoid fatal error in profileinfo.php when not configured.
 * Add a .htaccess to deleted images directory for additional protection against exposure of deleted files with known SHA-1 hashes on default installations.
 * Avoid streaming uploaded files to the user via index.php. This allows security-conscious users to serve uploaded files via a different domain, and thus client-side scripts executed from that domain cannot access the login cookies. Affects Special:Undelete, img_auth.php and thumb.php.
 * When streaming files via index.php, use the MIME type detected from the file extension, not from the data. This reduces the XSS attack surface.
 * Blacklist redirects via Special:Filepath. Such redirects exacerbate any XSS vulnerabilities involving uploads of files containing scripts.
 * Internationalisation updates.

MediaWiki 1.12.1

 * (bug 13522) Fix fatal error in Parser::extractTagsAndParams
 * (bug 12077) Fix HTML nesting for TOC
 * (bug 13532) Use proper timestamp call when reverting images
 * (bug 13649, 14084) Bad call to wfTimestamp
 * (bug 13770) Use Preprocessor_Hash by default to avoid missing DOM module errors
 * (bug 13442) API: Missing pages in prop=langlinks and prop=extlinks are now handled properly.
 * (bug 13482) API: Disabled search types handled properly
 * (bug 13836) API: Fixed fatal errors resulting from combining iiprop=metadata with format=xml
 * (bug 11633) API: Explicitly convert redirect titles to strings due to PHP's very weak typing on array keys.
 * API: Fixing main page display in meta=siteinfo
 * (bug 11719) API: Remove trailing blanks in YAML output.
 * (bug 13718) API: Return the proper continue parameter for cmsort=timestamp
 * Security: Work around misconfiguration by requiring strict comparisons for in_array in User::isAllowed.
 * Security: Fixed XSS vulnerability in useskin parameter.

MediaWiki 1.12.0
This is the quarterly branch release of MediaWiki for Winter 2008.

MediaWiki is now using a "continuous integration" development model with quarterly snapshot releases. The latest development code is always kept "ready to run", and in fact runs our own sites on Wikipedia.

Release branches will continue to receive security updates for about a year from first release, but nonessential bugfixes and feature developments will be made on the development trunk and appear in the next quarterly release.

Those wishing to use the latest code instead of a branch release can obtain it from source control: Download from SVN.

Changes since 1.12.0rc1:
 * (bug 13359) Double-escaping in Special:Allpages.
 * Localization updates.

MediaWiki 1.12.0rc1
This is a release candidate of the Winter 2008 quarterly snapshot release of MediaWiki.

MediaWiki is now using a "continuous integration" development model with quarterly snapshot releases. The latest development code is always kept "ready to run", and in fact runs our own sites on Wikipedia.

Release branches will continue to receive security updates for about a year from first release, but nonessential bugfixes and feature developments will be made on the development trunk and appear in the next quarterly release.

Those wishing to use the latest code instead of a branch release can obtain it from source control: Download from SVN.

Configuration changes in 1.12

 * Marking edits as bot edits with Special:Contributions?bot=1 now requires the markbotedit permission, rather than the rollback permission previously used. This permission is assigned by default to the sysop group.
 * MediaWiki now checks if serialized files are out of date. New configuration variable can be set to false to enable old behavior (i.e. to not check and assume they are always up to date).
 * The rollback permission can now be rate-limited using the normal mechanism.
 * New configuration variable.
 * Behavior of and  changed. New behaviour:
 * Granting the userrights privilege allows arbitrary changing of rights.
 * Without the userrights privilege, a user will be able to add and/or remove the groups specified in $wgAddGroups and $wgRemoveGroups for any groups they are in.
 * New permission userrights-interwiki for changing user rights on foreign wikis.
 * for groups that are hidden from Special:Listusers, etc.
 * : Automatically promote users who match specified criteria.
 * , : allow users to add or remove themselves from specified groups via Special:Userrights.
 * When has been enabled, PHP's Tidy module is now used if it is present, in preference to an external Tidy executable which may or may not be present. To force use of external Tidy even when the PHP module is available, set  to false.

New features in 1.12

 * (bug 10735) Add a warning for non-descriptive filenames at Special:Upload.
 * Add filepath:}} parser function to get full path to an uploaded file, complementing  fullurl:}} for pages.
 * (bug 11136) If using Postgres, search path is explicitly set if is not set to 'mediawiki', allowing multiple mediawiki instances per user.
 * (bug 11151) Add descriptive to revision history page.
 * (bug 5412) Add feed links for the site to all pages.
 * (bug 11353) Add ability to retrieve raw section content via action=raw.
 * (bug 6909) Show relevant deletion log lines when uploading a previously deleted file.
 * On SkinTemplate based skins (like MonoBook), omit confusing "edit"/"view source" tab entirely if the page doesn't exist and the user isn't allowed to create it.
 * Clarify instructions given when an exception is thrown.
 * AuthPlugin added strictUserAuth method to allow per-user override of the strict authentication behavior.
 * (bug 7872) Deleted revisions can now be viewed as diffs showing changes against the previous revision, whether currently deleted or live.
 * Added tooltips for the "Go" and "Search" buttons.
 * (bug 11649) Show input form when Special:Whatlinkshere has no parameters.
 * isValidEmailAddr hook added to User method of that name, to allow, e.g., restricting e-mail addresses to a specific domain.
 * Removed "Clear" link in watchlist editor tools, as people were afraid to click it. Existing clear links will fall back to the raw editor, which is very easy to clear your watchlist with.
 * (bug 1405) Add option to control patrolling for new articles on Special:Newpages.
 * LogLine hook added to allow formatting custom entries in Special:Log.
 * Support for Iranian calendar.
 * (bug 1401) Allow hiding logged-in users, bots and patrolled pages on Special:Newpages.
 * ChangesListInsertArticleLink hook added for adding extra article info to RC.
 * MediaWikiPerformAction hook added for diverting control after the main globals have been set up but before any actions have been taken.
 * BeforeWatchlist hook added for filtering or replacing watchlist.
 * SkinTemplateTabAction hook added for altering the properties of tab links.
 * OutputPage::getRedirect public method added.
 * (bug 11848, 12506) Allow URL parameters 'section', 'editintro' and 'preload' in Special:Mypage and Special:Mytalk.
 * Add ot=raw to Special:Allmessages.
 * Support for Hebrew calendar.
 * Support for Hebrew numerals in dates and times.
 * (bug 11315) Signatures can be configured in MediaWiki:Signature and MediaWiki:Signature-anon.
 * Signatures for anonymous users link to Special:Contributions page rather than user page.
 * Added --override switch for disabled pages in updateSpecialPages.php.
 * Provide a unique message (ipb_blocked_as_range) if unblock of a single IP fails because it is part of a blocked range.
 * (bug 3973) Use a separate message for the email content when an account is created by another user.
 * dumpTextPass.php can spawn fetchText.php as a subprocess, which should restart cleanly if database connections fail unpleasantly.
 * (bug 12028) Add Special:Listbots as shortcut for Special:Listusers/bot.
 * (bug 9633) Add a predefined list of delete reasons to the deletion form.
 * Show a warning message when creating/editing a user (talk) page but the user does not exist.
 * (bug 8396) Ignore out-of-date serialized message caches.
 * (bug 12195) Undeleting pages now requires 'undelete' permission.
 * (bug 11810) Localize displayed semicolons.
 * (bug 11657) Support for Thai solar calendar.
 * (bug 943) RSS feed for Recentchangeslinked.
 * Introduced AbortMove hook.
 * (bug 2919) Protection of nonexistent pages with regular protection interface.
 * Special:Upload now lists permitted/prohibited file extensions.
 * Split ambiguous filetype-badtype message into two new messages, filetype-unwanted-type and filetype-banned-type.
 * Added link to the old title in Special:Movepage.
 * On Special:Movepage, errors are now more noticeable.
 * It is now possible to change rights on other local wikis without the MakeSysop extension.
 * Add HTML ID's mw-read-only-warning and mw-anon-edit-warning to warnings when editing to allow CSS styling.
 * Parser now returns list of sections.
 * When a user is prohibited from creating a page, a title of "View source" makes no sense, and there should be no "Return to Page" link.
 * (bug 12486) Protected titles now give a warning for privileged editors.
 * (bug 9939) Special:Search now sets focus to search input box when no existing search is active.
 * For Special:Userrights, use GET instead of POST to search for users.
 * Allow subpage syntax for Special:Userrights, i.e., Special:Userrights/Name.
 * When submitting changes on Special:Userrights, show the full form again, not just the search box.
 * Added exception hooks.
 * (bug 12574) Allow bots to specify whether an edit should be marked as a bot edit, via the parameter 'bot'. (Default: '1')
 * (bug 12536) User should be able to get MediaWiki version from any page.
 * (bug 12622) A JavaScript constant to declare whether api.php is available.
 * Add caching to the AJAX search.
 * Add APCOND_INGROUPS.
 * Add DBA caching to installer.
 * (bug 18585) Added a bunch of parameters to the revertpage message.
 * Support redirects in image namespace.
 * (bug 10049) Prefix index search and namespaces in Special:Withoutinterwiki.
 * (bug 12668) Support for custom iPhone bookmark icon via.
 * Add option to include templates in Special:Export.
 * (bug 12655) Added config option to put sender address in Reply-To instead of From for user-to-user emails. This protects against SPF problems and privacy-leaking bounce messages when using mailers that set the envelope sender to the From header value.
 * (bug 11897) Add alias Special:CreateAccount & Special:Userlogin/signup for Special:Userlogin?type=signup.
 * (bug 12214) Add a predefined list of delete reasons to the file deletion form.
 * Merged backends for OpenSearch suggestions and AJAX search. Both now accept namespace prefixes, handle 'Media:' and 'Special:' pages, and reject interwiki prefixes. PrefixSearch class centralizes this code, and the backend part can be overridden by the PrefixSearchBackend hook.
 * (bug 10365) Localization of Special:Version.
 * When installing using Postgres, the Pl/Pgsql language is now checked for and installed when at the superuser level.
 * The default robot policy for the entire wiki is now configurable via the setting.
 * (bug 12239) Use different separators for autocomments.
 * (bug 12857) Patrol link on new pages should clear floats.
 * (bug 12968) Render redirect wikilinks in a redirect class for customization via user/site CSS.
 * hook added for altering the edit buttons below the edit box.

Bug fixes in 1.12

 * Subpages are now indexed for searching properly when using PostgreSQL.
 * (bug 3846) Suppress warnings from, e.g. open_basedir when scanning for ImageMagick, diff3 et al. during installation [patch by Jan Reininghaus].
 * (bug 7027) Shift handling of deletion permissions-checking to getUserPermissionsErrors.
 * Login and signup forms are now more correct for right-to-left languages.
 * (bug 5387) Block log items on RecentChanges don't make use of possible translations.
 * (bug 11211) Pass, as a parameter to the protectedpagetext interface message, the level of protection.
 * (bug 9611) Supply the blocker and reason for the cantcreateaccounttext message.
 * (bug 8759) Fixed bug where rollback was allowed on protected pages for wikis where rollback is given to non-sysops.
 * (bug 8834) Split off permission for editing user JavaScript and CSS from editinterface to a new permission key editusercssjs.
 * (bug 11266) Set fallback language for Fulfulde (ff) to French.
 * (bug 11179) Include image version deletion comment in public log.
 * Fixed notice when accessing special page without read permission and whitelist is not defined.
 * (bug 9252) Fix for tidy funkiness when using editintro mode.
 * (bug 4021) Fix for MySQL wildcard search.
 * (bug 10699) Fix for MySQL phrase search.
 * (bug 11321) Fix width of gallerybox when option "width=xxx" is used.
 * (bug 7890) Special:BrokenRedirects links deleted redirects to a non-existent page.
 * Fix initial statistics when installing: add correct values.
 * (bug 11342) Fix several 'returnto' links in permissions/error pages which linked to the main page instead of targetted page
 * Strike the link to the redirect rather than using an *asterisk in Special:Listredirects.
 * (bug 11355) Fix false positives in Safe Mode and other config detection when boolean settings are disabled with 'Off' via php_admin_value/php_value.
 * (bug 11292) Fixed unserialize errors with Postgres by creating special Blob object.
 * (bug 11363) Make all metadata fields bytea when using Postgres.
 * (bug 11331) Add buildConcat and use CASE not IF for DB compatibility. Make oldimage cascade delete via image table for Postgres, change fa_storage_key TEXT.
 * (bug 11438) Live Preview chops returned text
 * Show the right message on account creation when the user is blocked
 * (bug 11450) Fix creation of objectcache table on upgrade
 * Fix namespace selection after submit of Special:Newpages.
 * Make input form of Special:Newpages nicer for RTL wikis
 * (bug 11462) Fix typo in LanguageGetSpecialPageAliases hook name
 * (bug 11474) Fix unintentional fall-through in math error handling
 * (bug 11478) Fix undefined method call in file deletion interface
 * (bug 278) Search results no longer highlight incorrect partial word matches
 * Compatibility with incorrectly detected old-style DJVU mime types
 * (bug 11560) Fix broken HTML output from weird link nesting in edit comments. Nested links (as in image caption text) still don't work _right_ but they're less wrong
 * (bug 9718) Remove unnecessary css from main.css causing spacing issues on some browsers.
 * (bug 11574) Add an interface message loginstart, which, similarly to loginend, appears just before the login form. Patch by MinuteElectron.
 * Do not cache category pages if using 'from' or 'until'.
 * Created new hook getUserPermissionsErrors, to go with userCan changes.
 * Diff pages did not properly display css/js pages.
 * (bug 11620) Add call to User::isValidEmailAddr during accout creation.
 * (bug 11629) If $wgEmailConfirmToEdit is true, require people to supply an email address when registering.
 * (bug 11612) Days to show in recent changes cannot be larger than 7.
 * (bug 11131) Change filearchive width/height columns to int for Postgres
 * Support plural in undeleted{revisions,revisions-files,files}.
 * (bug 11343) If the database is read-only, ensure that undelete fails.
 * (bug 11690) Show revert link for page moves in Special:Log to allowed users only.
 * Initial-lowercase prefix checks in namespaceDupes.php now actually work.
 * Fix regression in LinkBatch.php breaking PHP 5.0.
 * (bug 11452) wfMsgExt uses sometimes wrong language object for parsing magic words when called with options parsemag or content.
 * (bug 11727) Support plural in 'historysize' message.
 * (bug 11744) Incorrect return value from Title::getParentCategories.
 * (bug 11762) Fix native language name of Akan (ak).
 * (bug 11722) Fix inconsistent case in unprotect tabs.
 * (bug 11795) Be more paranoid about confirming accept-encoding header is present.
 * (bug 11809) Use formatNum for more numbers.
 * (bug 11818) Fix native language name of Inuktitut (iu).
 * Remove all commas when parsing float numbers in sorted tables.
 * Limit text field of deletion, protection and user rights changes reasons to 255 characters (already restricted in the database).
 * In the deletion default reasons, calculate how much text to get from the article text, rather than getting 150 characters (which may be too much).
 * Add two messages for Special:Blockme which were used but undefined.
 * (bug 11921) Support plural in message number_of_watching_users_pageview.
 * If an IP address is blocked as part of a rangeblock, attempting to unblock the single IP should not unblock the entire range.
 * (bug 6695) Fix native language name of Southern Sotho (Sesotho) (st).
 * Make action=render follow redirects by default.
 * If restricted read access was enabled, whitelist didn't work with special pages which had spaces in theirs names.
 * If restricted read access was enabled, requests for non-existing special pages threw an exception.
 * Feeds for recent changes now provide correct URLs for the change, not just the page.
 * Check for if IP is blocked as part of a range when unblocking (see above bug- fix) was faulty. Now fixed.
 * Fixed wpReason URL parameter to action=delete.
 * Do not force a password for account creation by email.
 * Ensure that rate-limiting is applied to rollbacks.
 * Make a better rate-limiting error message (i.e. a normal MW error, rather than an "Internal Server Error").
 * Do not present an image bigger than the source when 'frameless' option is used (to be consistent with the 'thumb' option now).
 * Support for import log.
 * Make sure that the correct log entries are shown on Special:Userrights even for users with special characters in their names.
 * The number of watching users in watchlists was always reported as 1.
 * namespaceDupes.php no longer dies when coming across an illegal title.
 * (bug 12143) Do not show a link to patrol new pages for non existent pages.
 * (bug 12166) Fix XHTML validity for Special:Emailuser.
 * (bug 11346) Users who cannot edit a page can now no longer unprotect it.
 * (bug 451) Add a generic Traditional / Simplified Chinese conversion table, instead of a Traditional conversion with Taiwan variant, and a Simplified conversion with China variant.
 * (bug 12178) Fix wpReason parameter to action=delete, again.
 * Graceful behavior for updateRestrictions.php if a page already has records in the page_restrictions matching its old page_restrictions field. May help with odd upgrade issues or race condition.
 * (bug 11993) Remove contentsub "revision history"
 * (bug 11952) Ensure we quote_ident all schema names as needed inside of the DatabasePostgres.php file.
 * (bug 12184) Exceptions now sent to stderr instead of stdout for command-line scripts, making for cleaner reporting during batch jobs. PHP errors will also be redirected in most cases on PHP 5.2.4 and later, switching 'display_errors' to 'stderr' at runtime.
 * (bug 12148) Text highlight wasn't applied to cleanly deleted and added lines in diff output
 * (bug 10166) Fix a PHP warning in Language::getMagic
 * Only mark rollback edits as minor if the user can normally mark edits minor
 * Escape page names in the move successful page (e.g. for pages with two apostrophes).
 * (bug 12145) Add localized names of kk-variants
 * (bug 12259) Localize the numbers in deleted pages on the sysop view.
 * Set proper page title for successful file deletion.
 * (bug 11221) Do not show 'Compare selected versions' button for a history page with one revision only.
 * (bug 12267) Set the default date format to Thai solar calender for the Thai language.
 * (bug 10184) Extensions' stylesheets and scripts should be loaded before user-customized ones (like Common.css, Common.js).
 * (bug 12283) Special:Newpages forgets parameters.
 * (bug 12031) All namespaces doesn't work in Special:Newpages.
 * (bug 585) Only create searchindex replica table for parser tests if db is MySQL.
 * Allow --record option if parserTests.php to work when using Postgres.
 * (bug 12296) Simplify cache epoch in default LocalSettings.php.
 * (bug 12346) XML fix when body double-click and click handlers are present.
 * Fix regression -- missing feed links in sidebar on Special:Recentchanges.
 * (bug 12371) Handle more namespace case variants in namespaceDupes.php.
 * (bug 12380) Bot-friendly EditPage::spamPage.
 * (bug 8066) Spaces can't be entered in special page aliases.
 * Hide undo link if user can't edit article.
 * (bug 12416) Fix password setting for createAndPromote.php.
 * (bug 3097) Inconsistently usable titles containing HTML character entities are now forbidden. A run of cleanupTitles.php will fix up existing pages.
 * (bug 12446) Permissions check fix for undelete link.
 * (bug 12451) AJAX title normalization tweaks.
 * When a user creating a page is not allowed to either create the page nor edit it, all applicable reasons are now shown.
 * (bug 11428) Allow $wgScript inside $wgArticlePath when emulating PATH_INFO Fixes 'root'-style rewrite configurations.
 * (bug 12493) Removed hardcoded MAX_FILE_SIZE from Special:Import upload form.
 * (bug 12489) Special:Userrights listed in restricted section again.
 * (bug 12553) Fixed invalid XHTML in edit conflict screen.
 * (bug 12505) Fixed section=0 with action=raw.
 * (bug 12614) Do not log user rights change that didn't change anything.
 * (bug 12584) Don't reset cl_timestamp when auto-updating sort key on move.
 * (bug 12588) Fix selection in namespace selector on Special:Newpages.
 * Use only default options when generating RSS and Atom syndication links. This should help prevent infinite link loops that some software may follow, and will generally keep feed behavior cleaner.
 * (bug 12608) Unifying the spelling of getDBkey in the code.
 * (bug 12611) Bot flag ignored in recent changes.
 * (bug 12617) Decimal and thousands separators for Romanian.
 * (bug 12567) Fix for misformatted read-only messages on edit, protect. Also added proper read-only checks to several special pages. Have removed read-only checks from the general user permission framework.
 * Creating a site with a name containing '#' is no longer permitted, since the name will not work (but $wgSiteName is not checked if manually set).
 * (bug 12695) Suppress dvips verbiage from web server error log.
 * (bug 12716) Unprotecting a non-protected page leaves a log entry.
 * Log username blocks with canonical form of name instead of input form.
 * (bug 11593, 12719) Fixes for overzealous invocation of thumb.php. Non-image handlers and full-size images may now decline it, fixing mystery failures when using $wgThumbnailScriptPath.
 * (bug 12327) Comma in username no longer disrupts mail headers.
 * (bug 6436) Localization of Special:Import XML parser Error message(s).
 * Security fix for API on MSIE.
 * (bug 12768) Database query syntax error in maintenance/storage/compressOld.inc.
 * (bug 12753) Empty captions in MediaWiki:Sidebar result in PHP errors.
 * (bug 12790) Page protection is not logged when edit-protection is used and move-protection is not.
 * (bug 12793) Fix for restricted namespaces/pages in Special:Export.
 * Fix for Special:Export so it doesn't ignore the page named '0'.
 * Don't display rollback link if the user doesn't have all required permissions.
 * The comment of a time-limited protection now contains the date in the default format.
 * (bug 12880) wfLoadExtensionMessages does not use $fallback from MessagesXx.php.
 * (bug 12885) Correction for Russian convertPlural function.
 * (bug 12768) Make DatabasePostgres->hasContraint schema aware.
 * (bug 12735) Truncate usernames in comments using mb_ functions.
 * (bug 12892) Poor tab indexing on "delete file" form.
 * (bug 12660) When creating an account by e-mail, do not send the creator's IP address.
 * (bug 12931) Fix wrong global variable in Special:Version.
 * (bug 12919) Use 'deletedrevision' message as content when deleting an old file version.
 * (bug 12952) Using Nosuchusershort instead of Nosuchuser when account creation is disabled.
 * (bug 12869) Magnify icon alignment should be adjusted using linked CSS.
 * Fixing message cache updates for MediaWiki messages moves.
 * (bug 12815) Signature timestamps were always in UTC, even if the timezone code in parentheses after them claimed otherwise.
 * (bug 12732) Fix installer and searching to handle built-in tsearch2 for Postgres.
 * (bug 12784) Change "bool" types to smallint to handle Postgres 8.3 strictness.
 * (bug 12301) Allow maintenance/findhooks.php to search hooks in multiple directories.
 * (bug 7681, 11559) Cookie values no longer override GET and POST variables.
 * (bug 5262) Fully-qualified no longer corrupted on XML feeds.
 * (bug 3269) Inaccessible titles ending in '/.' or '/..' now forbidden.
 * (bug 12935, 12981) Fully-qualify archive URLs in delete, revert messages.
 * (bug 12938) Fix template expansion and 404 returns for action=raw with section.
 * (bug 11567) Fix error checking for PEAR::Mail. UserMailer::send now returns true-or-WikiError, which seems to be the calling convention expected by half its callers already.
 * (bug 12846) IE rtl.css issue in RTL wikis Special:Preferences when selecting an LTR user language.
 * (bug 13005) DISPLAYTITLE does not work on preview.
 * (bug 13004) Fix error on Postgres searches that return too many results.
 * (bug 13022) Fix upload from URL on PHP 5.0.x.
 * (bug 13139, 13074) Fix request data for parameters with numeric names.
 * (bug 13086) Trackbacks were returning invalid XML (extra whitespace).
 * (bug 12430) Fix call to private method LinkFilter::makeRegex fatal error in maintenance/cleanupSpam.php.
 * (bug 13211) Don't break edit buttons when Image namespace includes apostrophe.
 * Fix regression with upgrades from 1.4 or below.
 * Fix regression: make dumpUploads.php work again.
 * dumpUploads.php options now actually supported.
 * wfRelativePath no longer includes spurious ".." when base path is "/".
 * wfRelativePath now returns full path for differing Windows drives.
 * (bug 13274) Change link for message to ucfirst.

Parser changes in 1.12
For help with migration to the MediaWiki 1.12 parser, please visit: Migration to the new preprocessor.

The parser pass order has changed from
 * Extension tag strip and render
 * HTML normalisation and security
 * Template expansion
 * Main section...

to


 * Template and extension tag parse to intermediate representation
 * Template expansion and extension rendering
 * HTML normalisation and security
 * Main section...

The main effect of this for the user is that the rules for uncovered syntax have changed.

Uncovered main-pass syntax, such as HTML tags, are now generally valid, whereas previously in some cases they were escaped. For example, you could have "  " in another template, and put them together to make a valid  tag. Previously the result would have been "&lt;table&gt;".

Uncovered preprocessor syntax is generally not recognized. For example, if you have "" in Template:B, then "" will be converted to a literal "" rather than the contents of Template:Ab. This was the case previously in HTML output mode, and is now uniformly the case in the other modes as well. HTML-style comments uncovered by template expansion will not be recognized by the preprocessor and hence will not prevent template expansion within them, but they will be stripped by the following HTML security pass.

Bug 5678 has been fixed. This has a number of user-visible effects related to the removal of this double-parse. Please see the wiki page for examples.

Message transformation mode has been removed, and replaced with "preprocess" mode. This means that some MediaWiki namespace messages may need to be updated, especially ones which took advantage of the terribly counterintuitive behavior of the former message mode.

The header identification routines for section edit and for numbering section edit links have been merged. This removes a significant failure mode and fixes a whole category of bugs (tracked by bug #4899). Wikitext headings uncovered by template expansion will still be rendered into a heading tag, and will get an entry in the TOC, but will not have a section edit link. HTML-style headings will also not have a section edit link. Valid wikitext headings present in the template source text will get a template section edit link. This is a major break from previous behavior, but I believe the effects are almost entirely beneficial.

The main motivation for making these changes was performance. The new two-pass preprocessor can skip "dead branches" in template expansion, such as unfollowed #switch cases and unused defaults for template arguments. This provides a significant performance improvement in template-heavy test cases taken from Wikipedia. Parser function hooks can participate in this performance improvement by using the new SFH_OBJECT_ARGS flag during registration.

The pre-expand include size limit has been removed, since there's no efficient way to calculate such a figure, and it would now be meaningless for performance anyway. The "preprocessor node count" takes its place, with a generous default limit.

The context in which XML-style extension tags are called has changed, so extensions which make use of the parser state may need compatibility changes.

The new preprocessor syntax has been documented in Backus-Naur Form at Preprocessor ABNF.

The ExpandTemplates extension now has the ability to generate an XML parse tree from wikitext source. This parse tree corresponds closely to the grammar documented on that page.

API changes in 1.12
Full API documentation is available at API.


 * (bug 11275) Enable descending sort in categorymembers.
 * (bug 11308) Allow the API to output the image metadata.
 * (bug 11296) Temporary fix for escaping of ampersands inside links in pretty-printed help document.
 * (bug 11405) Expand templates implementation in the API.
 * (bug 11218) Add option to feedwatchlist to display multiple revisions for each page.
 * (bug 11404) Provide name of exception caught in error code field of internal api error messages.
 * (bug 11534) rvendid doesn't work.
 * Fixed rvlimit of the revisions query to only enforce the lower query limit if revision content is requested.
 * Include svn revision number (if install is checked-out from svn) in siteinfo query.
 * (bug 11173) Allow limited wikicode rendering via api.php.
 * (bug 11572) API should provide interface for expanding templates.
 * (bug 11569) Login should return the cookie prefix.
 * (bug 11632) Breaking change: Specify the type of a change in the recentchanges list as 'edit', 'new', 'log' instead of 0, 1, 2, respectively.
 * Compatibility fix for PHP 5.0.x.
 * Add rctype parameter to list=recentchanges that filters by type.
 * Add apprtype and apprlevel parameters to filter list=allpages by protection types and levels.
 * Add apdir parameter to enable listing all pages from Z to A.
 * (bug 11721) Use a different title for results than for the help page.
 * (bug 11562) Added a user_registration parameter/field to the list=allusers query.
 * (bug 11588) Preserve document structure for empty dataset in backlinks query.
 * Outputting list of all user preferences rather than having to request them by name.
 * (bug 11206) api.php should honor maxlag.
 * Make prop=info check for restrictions in the old format too.
 * Add apihighlimits permission, default for sysops and bots.
 * Add limit=max to use maximal limit.
 * Add action=parse to render parser output. Use it instead of action=render which has been removed.
 * Add rvtoken=rollback to prop=revisions.
 * Add meta=allmessages to get messages from site's messages cache.
 * Use bold and italics highlighting only in API help.
 * Added action={block,delete,move,protect,rollback,unblock,undelete} and list={blocks,deletedrevs}.
 * Fixed sessionid attribute in action=login.
 * Standardized limits. Revisions and Deletedrevisions formerly using 200 / 10000, now 500 / 5000, in line with other modules.
 * Added list=allcategories module.
 * (bug 12321) API list=blocks reveals private data.
 * Fix output of wfSajaxSearch.
 * (bug 12413) meta=userinfo missing tag.
 * Add list of sections to action=parse output.
 * Added action=logout.
 * Added cascade flag to prop=info&inprop=protections.
 * Added wlshow parameter to list=watchlist, similar to rcshow (list=recentchanges).
 * Added support for image thumbnailing to prop=imageinfo.
 * action={login,block,delete,move,protect,rollback,unblock,undelete} now must be POSTed.
 * prop=imageinfo interface changed: iihistory replaced by iilimit, iistart and iiend parameters.
 * Added amlang parameter to meta=allmessages.
 * Added apfilterlanglinks parameter to list=allpages, replacing query.php?what=nolanglinks.
 * (bug 12718) Added action=paraminfo module that provides information about API modules and their parameters.
 * Added iiurlwidth and iiurlheight parameters to prop=imageinfo.
 * Added format=txt and format=dbg, imported from query.php.
 * Added uiprop=editcount to meta=userinfo.
 * Added list=users which fetches user information.
 * Added list=random which fetches a list of random pages.
 * Added page parameter to action=parse to facilitate parsing of existing pages.
 * Added uiprop=ratelimits to meta=userinfo.
 * Added siprop=namespacealiases to meta=siteinfo.
 * Made multiple values for ucuser possible in list=usercontribs.
 * (bug 12944) Added cmstart and cmend parameters to list=categorymembers.
 * Allow queries to have a where range that does not match the range field.

Languages updated in 1.12

 * Afrikaans (af)
 * Akan (ak) (new)
 * Amharic (am) (new)
 * Aragonese (an)
 * Old English (ang) (new)
 * Arabic (ar)
 * Aramaic (arc)
 * Mapudungun (arn) (new)
 * Assamese (as)
 * Asturian (ast)
 * Avaric (av)
 * Kotava (avk) (new)
 * Aymara (ay)
 * Samogitian (bat-smg)
 * Boarisch (bar)
 * Bikol Central (bcl)
 * Belarusian (be)
 * Belarusian Taraskievica orthography (be-tarask)
 * Bulgarian (bg)
 * Bislama (bi) (new)
 * Bamanankan (bm)
 * Bengali (bn)
 * Bishnupriya Manipuri (bpy)
 * Breton (br)
 * Buginese (bug) (new)
 * Catalan (ca)
 * Zamboangueño (cbk-zam) (new)
 * Min Dong (cdo) (new)
 * Chechen (ce)
 * Cebuano (ceb) (new)
 * Cherokee (chr) (new)
 * Corsican (co) (new)
 * Crimean Tatar (Cyrillic) (crh-cyrl) (new)
 * Crimean Tatar (Latin) (crh-latn) (new)
 * Czech (cs)
 * Cassubian (csb)
 * Old Church Slavonic (cu)
 * Welsh (cy)
 * Danish (da)
 * German (de)
 * German (de-formal) (new)
 * Zazaki (diq) (new)
 * Lower Sorbian (dsb) (new)
 * Middle Dutch (dum) (new)
 * Divehi (dv)
 * Ewe (ee) (new)
 * Greek (el)
 * Emiliano-Romagnolo (eml)
 * English (en)
 * Spanish (es)
 * Estonian (et)
 * Euskara (eu)
 * Extremaduran (ext)
 * Finnish (fi)
 * Persian (fa)
 * Fulah (ff)
 * Võro (fiu-vro)
 * Fijian (fj) (new)
 * Faroese (fo)
 * French (fr)
 * Cajun French (frc)
 * Franco-Provençal (frp)
 * Frisian (fy)
 * Irish (ga)
 * Gagauz (gag) (new)
 * Gön-gnŷ (gan) (new)
 * Scottish Gaelic (gd) (new)
 * Galician (gl)
 * Gilaki (glk) (new)
 * Gothic (got) (new)
 * Ancient Greek (grc) (new)
 * Swiss German (gsw)
 * Hakka (hak)
 * Hawaiian (haw) (new)
 * Hebrew (he)
 * Croatian (hr)
 * Upper Sorbian (hsb)
 * Haitian Creole French (ht)
 * Hungarian (hu)
 * Armenian (hy)
 * Interlingua (ia)
 * Indonesian (id)
 * Interlingue (ie) (new)
 * Igbo (ig) (new)
 * Eastern Canadian (Unified Canadian Aboriginal Syllabics) (ike-cans) (new)
 * Eastern Canadian (Latin) (ike-latn) (new)
 * Ingush (inh) (new)
 * Ido (io) (new)
 * Icelandic (is)
 * Italian (it)
 * Japanese (ja)
 * Jutish (jut) (new)
 * Georgian (ka)
 * Kara-Kalpak (kaa)
 * Kabyle (kab)
 * Kazakh (kk)
 * Kazakh Arabic (kk-arab) (new)
 * Kazakh (China) (kk-cn)
 * Kazakh Cyrillic (kk-cyrl) (new)
 * Kazakh (Kazakhstan) (kk-kz)
 * Kazakh Latin (kk-latn) (new)
 * Kazakh (Turkey) (kk-tr)
 * Kalaallisut (kl) (new)
 * Kannada (kn)
 * Korean (ko)
 * Kölsch (ksh)
 * Kurdish (Arabic) (ku-arab)
 * Kurdish (Latin) (ku-latn)
 * Cornish (kw) (new)
 * Kirghiz (ky) (new)
 * Latin (la)
 * Ladino (lad) (new)
 * Luxembourgish (lb) (new)
 * Lingua Franca Nova (lfn) (new)
 * Lak (lbe) (new)
 * Ganda (lg)
 * Limbugian (li)
 * Líguru (lij) (new)
 * Lozi (loz) (new)
 * Lingala (ln)
 * Lao (lo)
 * Lithuanian (lt)
 * Maithili (mai) (new)
 * Moksha (mdf) (new)
 * Malagasy (mg) (new)
 * Malayalam (ml)
 * Macedonian (mk)
 * Marathi (mr)
 * Malay (ms)
 * Erzya (myv) (new)
 * Nauru (na) (new)
 * Nahuatl (nah)
 * Min-nan (nan)
 * Napolitan (nap)
 * Low Saxon (nds)
 * Dutch Low Saxon (nds-nl)
 * Nepali (ne)
 * Newari (new) (new)
 * Dutch (nl)
 * Norwegian (nynorsk) (nn)
 * Norwegian (bokmål)‬ (no)
 * Novial (nov) (new)
 * Northern Sotho (nso) (new)
 * Occitan (oc)
 * Pangasinan (pag) (new)
 * Pampanga (pam) (new)
 * Papiamento (pap) (new)
 * Deitsch (pdc) (new)
 * Pfälzisch (pfl) (new)
 * Polish (pl)
 * Piemontèis (pms)
 * Pontic (pnt) (new)
 * Pashto (ps)
 * Portugese (pt)
 * Quechua (qu)
 * Rhaeto-Romance (rm) (new)
 * Romanian (ro)
 * Russian (ru)
 * Megleno-Romanian (ruq) (new)
 * Megleno-Romanian (Cyrillic script) (ruq-cyrl) (new)
 * Megleno-Romanian (Greek script) (ruq-grek) (new)
 * Megleno-Romanian (Latin script) (ruq-latn) (new)
 * Sakha (sah)
 * Sardinian (sc)
 * Sicilian (scn)
 * Scots (sco) (new)
 * Sindhi (sd)
 * Sassarese (sdc) (new)
 * Seri (sei) (new)
 * Sango (sg) (new)
 * Tachelhit (shi)
 * Sinhalese (si) (new)
 * Slovak (sk)
 * Samoan (sm) (new)
 * Southern Sami (sma) (new)
 * Serbian (Cyrillic) (sr-ec)
 * Swati (ss) (new)
 * Southern Sotho (st) (new)
 * Saterland Frisian (stq) (new)
 * Sundanese (su)
 * Swedish (sv)
 * Swahili (sw) (new)
 * Tamil (ta)
 * Teluga (te)
 * Tetun (tet) (new)
 * Tajik (tg)
 * Thai (th)
 * Tagalog (tl) (new)
 * Tonga (to) (new)
 * Turkish (tr)
 * Tuvinian (tyv)
 * Uyghur (ug)
 * Uzbek (uz)
 * Venitian (vec)
 * Vietnamese (vi)
 * West Flemish (vls)
 * Volapük (vo)
 * Walloon (wa)
 * Wolof (wo)
 * Wu (wuu) (new)
 * Xhosa (xh) (new)
 * Mingrelian (xmf) (new)
 * Yiddish (yi)
 * Yoruba (yo) (new)
 * Cantonese (yue)
 * Zhuang (za)
 * Zealandic (zea)
 * Chinese (zh)
 * Old Chinese/Late Time Chinese (zh-classical)
 * Chinese (Simplified) (zh-hans)
 * Chinese (Traditional) (zh-hant)
 * Chinese (Taiwan) (zh-tw)
 * Zulu (zu) (new)

Compatibility
MediaWiki 1.12 requires PHP 5 (5.1 recommended). PHP 4 is no longer supported.

PHP 5.0.x fails on 64-bit systems due to serious bugs with array processing: http://bugs.php.net/bug.php?id=34879. Upgrade affected systems to PHP 5.1 or higher.

MySQL 3.23.x is no longer supported; some older hosts may need to upgrade. At this time we still recommend 4.0, but 4.1/5.0 will work fine in most cases.

Upgrading
1.12 has several database changes since 1.11, and will not work without schema updates.

If upgrading from before 1.7, you may want to run refreshLinks.php to ensure new database fields are filled with data.

If upgrading from before 1.11, and you are using a wiki as a commons repository, make sure that it is updated as well. Otherwise, errors may arise due to database schema changes.

If you are upgrading from MediaWiki 1.4.x or earlier, some major database changes are made, and there is a slightly higher chance that things could break. Don't forget to always back up your database before upgrading!

See the file UPGRADE for more detailed upgrade instructions.

Caveats
Some output, particularly involving user-supplied inline HTML, may not produce 100% valid or well-formed XHTML output. Testers are welcome to set = "application/xhtml+xml"; to test for remaining problem cases, but this is not recommended on live sites. (This must be set for MathML to display properly in Mozilla.)

For notes on 1.11.x and older releases, see HISTORY.

Online documentation
Documentation for both end-users and site administrators is currently being built up on this wiki, and is covered under the GNU Free Documentation License (except for pages that explicitly state that their contents are in the public domain): see Documentation.

Mailing list

 * A MediaWiki-l mailing list has been set up distinct from the Wikipedia wikitech-l list: mediawiki-l.
 * A low-traffic announcements-only list is also available: mediawiki-announce.

It's highly recommended that you sign up for one of these lists if you're going to run a public MediaWiki, so you can be notified of security fixes.

IRC help
There's usually someone online in #mediawiki on irc.freenode.net.