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This extension is bundled with MediaWiki 1.18 and above. Thus you do not have to download it again.
MediaWiki extensions manualManual:Extensions
Crystal Clear action run.png

Release status:Extension status stable

ImplementationTemplate:Extension#type Page action
DescriptionTemplate:Extension#description Adds CAPTCHAs for page saves and other user actions
Author(s)Template:Extension#username Brion Vibber and others
Latest versionTemplate:Extension#version 1.3 (2014-12-05)
MediaWikiTemplate:Extension#mediawiki 1.21+
PHPTemplate:Extension#php 5.3+
Database changesTemplate:Extension#needs-updatephp No
LicenseTemplate:Extension#license GNU General Public License 2.0 or later
  • $wgCaptchaClass
  • $wgCaptchaWhitelistIP
  • $wgCaptcha
  • $wgCaptchaTriggers
  • $wgCaptchaTriggersOnNamespace
  • $wgCaptchaStorageClass
  • $wgCaptchaSessionExpiration
  • $wgCaptchaBadLoginExpiration
  • $ceAllowConfirmedEmail
  • $wgCaptchaBadLoginAttempts
  • $wgCaptchaWhitelist
  • $wgCaptchaRegexes
  • $wgCaptchaQuestions
  • $wgReCaptchaPublicKey
  • $wgReCaptchaPrivateKey
Added rightsTemplate:Extension#rights


Hooks usedTemplate:Extension#hook

Translate the ConfirmEdit extension if it is available at translatewiki.net

Check usage and version matrix.


Open tasks · Report a bug

The ConfirmEdit extension lets you use various different CAPTCHA techniques, to try to prevent spambots and other automated tools from editing your wiki, as well as to foil automated login attempts that try to guess passwords.

ConfirmEdit ships with several techniques/modules to generate captcha.

Module Description Effectiveness at stopping spam
SimpleCaptcha Users have to solve a simple math problem. Low
FancyCaptcha Users have to identify a series of characters, displayed in a stylized way. Low
MathCaptcha Users have to solve a math problem that's displayed as an image. Low
QuestyCaptcha Users have to answer a question, out of a series of questions defined by the administrator(s). Very high, until cracked
ReCaptcha Users have to identify a series of characters, either visually or audially, from a widget provided by the reCAPTCHA service. Low
ReCaptcha NoCaptcha Users are presented with a JavaScript-based check of humanity. If the check is failed, a puzzle is presented. High

Some of these modules require additional setup work:

  • MathCaptcha requires both the presence of TeX and, for versions of MediaWiki after 1.17, the Math extension;
  • FancyCaptcha requires running a preliminary setup script in Python;
  • and reCAPTCHA requires obtaining API keys.

Caveats: CAPTCHAs reduce accessibility and cause inconvenience to human users. In addition, they are not 100% effective against bots, and they will not protect your wiki from spammers who are willing and able to use human labor to get through the CAPTCHAs. You may wish to use ConfirmEdit in conjunction with other anti-spam features. Regardless of the solution you use, if you have a publicly-editable wiki it's important to keep monitoring the "Recent changes" page.

Starting October 6, 2014 the available Asirra module is no longer functional due to the discontinuation of the underlying Asirra service.[1]


Note Note: ConfirmEdit may not work if used with a MediaWiki version different from the one specified when downloading via the "Extension distributor".

  • Download and place the file(s) in a directory called ConfirmEdit in your extensions/ folder.
  • Add the following code at the bottom of your LocalSettings.php:
require_once "$IP/extensions/ConfirmEdit/ConfirmEdit.php";
  • Enable the CAPTCHA type which should be used
  • Configure as needed
  • YesY Done - Navigate to Special:Version on your wiki to verify that the extension is successfully installed.

CAPTCHA types[edit]

There are numerous different CAPTCHA types included with ConfirmEdit.


This module presents a question and the user supplies the answer. You provide the questions in the configuration. This module has proven to offer a strong mechanism against spam bots; it also should have the advantage of a better accessibility, as textual questions can be read by text-to-speech software allowing visually impaired users (but not bots) to answer correctly.

Add the following to LocalSettings.php to enable this CAPTCHA, editing the Q&A:

// If your MediaWiki version is 1.25 or higher, use this line:
wfLoadExtensions( array( 'ConfirmEdit', 'ConfirmEdit/QuestyCaptcha' ) );

// Else use these lines:
require_once "$IP/extensions/ConfirmEdit/ConfirmEdit.php";
require_once "$IP/extensions/ConfirmEdit/QuestyCaptcha.php";

// Add your questions in LocalSettings.php using this format:
$wgCaptchaQuestions = array(
	'What is the capital of France?' => 'Paris',
	'What is the capital of Spain' => 'MADRID', // Answers are case insensitive
	'What is the name of this wiki?' => $wgSitename, // You can use variables
	'How many fingers does a hand have?' => array( 5, 'five' ), // A question may have many answers

It will randomly choose a question from those supplied. The minimum is one.

  • QuestyCaptcha is case-insensitive. If the answer is "Paris" and the user writes "paris", or if the answer is "paris" and the user writes "Paris", it will still work.
  • If the answer has a special character like "ó", you may write an answer with "ó" and another without, just in case. For example if the answer is "canción" you can use array( 'cancion', 'canción' ) in case the user is lazy (or ignorant) and writes "cancion".
  • The answer must be easy to guess for a human interested in your wiki, but not by an automatic program. Ideally, it should not be contained in the text of the question; you can try and edit the captcha help messages[2] and provide the solution to the captcha response there.
  • Just change the questions when/if they start proving ineffective; this may never happen if your wiki is not specifically targeted.
  • Don't ever reuse questions already used by you or others in the past: spambots are known to remember a question and its answer forever once they broke it.
  • You can get even smarter, with questions like «What is the output of "date -u +%V`uname`|sha256sum|sed 's/\W//g'"?».
  • And other dynamic questy captchas. DO NOT use an exact copy of the dynamic questions from the link -- they've been cracked by spammers. However other dynamic questions in the style of the questions presented are highly effective.


Example screenshot of ReCaptcha
As noted in the ReCaptcha FAQ, Google does not support the ReCaptcha version 1 anymore, on which this CAPTCHA module depends on. You should consider upgrading to version 2 of ReCaptcha (see the ReCaptchaNoCaptcha module). This module will be removed from ConfirmEdit in the near future (see task T142133).

This module uses the "reCAPTCHA" widget/service. In addition to providing a CAPTCHA, it performs a valuable service because it helps to digitize old books.

To use this module, first go here and obtain a public and private key for your wiki.

Add the following to LocalSettings.php:

// Use this line ONLY if your MediaWiki version is 1.25 or newer:
wfLoadExtensions( array( 'ConfirmEdit', 'ConfirmEdit/ReCaptcha' ) );

// Use these two lines ONLY if your MediaWiki version is older than 1.25:
require_once "$IP/extensions/ConfirmEdit/ConfirmEdit.php";
require_once "$IP/extensions/ConfirmEdit/ReCaptcha.php";

$wgCaptchaClass = 'ReCaptcha';
$wgReCaptchaPublicKey = 'your public key here';
$wgReCaptchaPrivateKey = 'your private key here';
  • Recaptcha is only in the ConfirmEdit versions bundled with MediaWiki 1.18 and above. Earlier versions do not have the reCAPTCHA PHP files.
  • Unfortunately, as of 2011, some spammers appear to have figured out a way to bypass it, either through character recognition or by using humans. For that reason, it is not necessarily recommended.
  • Part of the weakness of the ReCaptcha module is that ConfirmEdit doesn't include any penalty mechanism, so spam bots can simply keep trying to bypass the CAPTCHA until they get through. This is an issue that is strongly worth addressing in some way.
  • ReCaptcha creates a partial dependence on user-side JavaScript, as well as a requirement for sound or graphics. It also localises poorly in most less-often used languages.
  • Regardless of its strengths or weaknesses, reCAPTCHA can't be implemented on Wikimedia wikis because it produces a third-party dependency.

ReCaptcha (NoCaptcha)[edit]

The ReCaptchaNoCaptcha module was introduced in the MediaWiki release 1.26; you can't use it in older versions of ConfirmEdit and MediaWiki.

The new generation of ReCaptcha, called NoCaptcha, was introduced by Google back in December 2014[3] and reduces the need for humans to solve a CAPTCHA. Based on a user-side JavaScript (which can't be controlled by the user the administrator), reCaptcha tries to identify the site user as a human by analyzing his browsing behavior on the page. The user then has to click an "I'm not a robot" checkbox and (in the best case) doesn't have to do anything further to prove he's a human. However, in some cases, the user still has to solve a CAPTCHA image.

This module implements the new ReCaptcha NoCaptcha solution in ConfirmEdit. You still need a public and a secret key (which you can retrieve from the ReCaptcha admin panel) and install the plugin with:

wfLoadExtensions( array( 'ConfirmEdit', 'ConfirmEdit/ReCaptchaNoCaptcha' ) );
$wgCaptchaClass = 'ReCaptchaNoCaptcha';
$wgReCaptchaSiteKey = 'your public/site key here';
$wgReCaptchaSecretKey = 'your private key here';

There is an additional configuration option for this module, $wgReCaptchaSendRemoteIP (default: false), which, if set to true, sends the IP address of the current user to a server from Google while verifying the CAPTCHA. You can improve the privacy for your users if you keep this set to "false". However, remember, that this module adds a client side JavaScript code, directly loaded from a server from Google, which already can collect the IP address of the user (combined with other data, too) and can not be limited by a configuration option.

Not recommended[edit]

Warning Warning: The following types are used by very few wikis outside WMF if any, probably because of scarce effectiveness.

SimpleCaptcha (calculation)[edit]

a simple math question.

This is the default CAPTCHA. This module provides a simple addition or subtraction question for the user.

Add the following lines to LocalSettings.php in the root of your MediaWiki to enable this CAPTCHA:

$wgCaptchaClass = 'SimpleCaptcha';

Note that the display of a trivial maths problem as plaintext yields a captcha which can be trivially solved by automated means; as of 2012, sites using SimpleCaptcha are receiving significant amounts of spam and many automated registrations of spurious new accounts. VisualMathCaptcha is also relatively easily defeated. Wikis currently using this as the default should therefore migrate to one of the other CAPTCHAs.


FancyCaptcha screenshot.png

This module displays a stylized image of a set of characters. The Python Imaging Library must be installed in order to create the set of images initially, but isn't needed after that (can be installed with pip install pil in most environments).

  1. Add the following lines to LocalSettings.php in the root of your MediaWiki installation:
    MediaWiki version is 1.25 or newer:
    wfLoadExtensions( array( 'ConfirmEdit', 'ConfirmEdit/FancyCaptcha' ) );
    $wgCaptchaClass = 'FancyCaptcha';
    MediaWiki version is older than 1.25:
    require_once "$IP/extensions/ConfirmEdit/ConfirmEdit.php";
    require_once "$IP/extensions/ConfirmEdit/FancyCaptcha.php";
    $wgCaptchaClass = 'FancyCaptcha';
  2. In LocalSettings.php, set the variable $wgCaptchaDirectory to the directory where you will store Captcha images. Below it set $wgCaptchaSecret to your passphrase.
  3. Create the images by running the following, where:
    • font is a path to some font, for instance AriBlk.TTF.
    • wordlist is a path to some word list, for instance /usr/share/dict/words. (Note: on Debian/Ubuntu, the 'wbritish' and 'wamerican' packages provide such lists. On Fedora, use the 'words' package).
    • key is the the exact passphrase you set $wgCaptchaSecret to. Use quotes if necessary.
    • output is the path to where the images should be stored (defined in $wgCaptchaDirectory).
    • count is how many images to generate.
    python /path/to/captcha.py --font=<font> --wordlist=<wordlist> --key=<key> --output=<output> --count=<count>
    • An example, assuming you're in the extensions/ConfirmEdit directory (font location from Ubuntu 6.06, probably different on other operating systems):
    python captcha.py --font=/usr/share/fonts/truetype/freefont/FreeSans.ttf --wordlist=/usr/share/dict/words --key=FOO --output=../../../captcha --count=100
    • If you are not satisfied with the results of the words you've generated you can simply remove the images and create a new set. Comic_Sans_MS_Bold.ttf seems to generate relatively legible words, and you could also edit the last line of captcha.py to increase the font size from the default of 40.
  4. Put the images you get into captcha directory in your installation
  5. Edit your wiki's LocalSettings.php: specify full path to your captcha directory in $wgCaptchaDirectory and secret key you've been using while generating captures in $wgCaptchaSecret
$wgCaptchaDirectory = "/.php-data/my-wiki.org/wiki/captcha";
$wgCaptchaDirectoryLevels = 0; // Set this to a value greater than zero to break the images into subdirectories
$wgCaptchaSecret = "FOO"; // same value you used in --key option in captcha.py

See also wikitech:Generating CAPTCHAs for how Wikimedia Foundation does it.

How to avoid common problems running Python[edit]
  1. Install the most recent version of Python Imaging Library (PIL).
  2. Make the installation of Python on a short folder name. Like C:\Python\
  3. Create a folder like C:\Ex and place files CAPTCHA.py / FONT.ttf / LIST.txt into the folder.
  4. To execute easily, run the following example as a batch file:
C:\python\python.exe C:\Ex\CAPTCHA.py --font C:\Ex\FONT.ttf --wordlist C:\Ex\LIST.txt --key=YOURPASSWORD --output C:\Ex\ --count=20

Using Pillow instead of PIL[edit]

You can use the Pillow Library (can be installed with pip install pillow or apt-get install python-pillow in most environments) instead of the (old) Python Imaging Library (PIL) by simply changing the following lines in the file captcha.py (included in the extension folder of ConfirmEdit):

Change this lines in captcha.py: (cp. Porting existing PIL-based code to Pillow)

        import Image
	import ImageFont
	import ImageDraw
	import ImageEnhance
	import ImageOps
        import ImageMath

To this:

        from PIL import Image
	from PIL import ImageFont
	from PIL import ImageDraw
	from PIL import ImageEnhance
	from PIL import ImageOps
	from PIL import ImageMath


This requires the Math extension to be installed.
Until MediaWiki 1.18 this was part of MediaWiki; in later versions you need to install it manually. See also Extension:Math

This module generates an image using TeX to ask a basic math question.

Set the following to enable this CAPTCHA:

// Use this line ONLY if your MediaWiki version is 1.25 or newer:
wfLoadExtension( 'ConfirmEdit/MathCaptcha' );
// Use this line ONLY if your MediaWiki version is older than 1.25:
require_once "$IP/extensions/ConfirmEdit/MathCaptcha.php";
$wgCaptchaClass = 'MathCaptcha';

See the readme file in the math folder to install this captcha.

Outside extensions[edit]

See each extension's documentation for how to install and configure it.


The extension VisualMathCaptcha (now abandoned) had been used in conjunction with ConfirmEdit, but is easily defeated and not worth the effort.


KeyCAPTCHA can be one of the more effective alternatives to ConfirmEdit, but at a price... it requires the user support both JavaScript and (one of) HTML5/Flash in order to be able to solve a graphic of a jigsaw puzzle. This breaks accessibility for visually impaired users, as well as breaking text-only or text-to-speech browsers.

KeyCAPTCHA is proprietary and dependent on an external server; if the company withdraws the product, new user registrations break immediately.


ConfirmEdit introduces a 'skipcaptcha' permission type to wgGroupPermissions. This lets you set certain groups to never see CAPTCHAs. All of the following can be added to localsettings.php.

Defaults from ConfirmEdit.php:

$wgGroupPermissions['*'            ]['skipcaptcha'] = false;
$wgGroupPermissions['user'         ]['skipcaptcha'] = false;
$wgGroupPermissions['autoconfirmed']['skipcaptcha'] = false;
$wgGroupPermissions['bot'          ]['skipcaptcha'] = true; // registered bots
$wgGroupPermissions['sysop'        ]['skipcaptcha'] = true;

To skip captchas for users that confirmed their email, you need to set both:

$wgGroupPermissions['emailconfirmed']['skipcaptcha'] = true;
$ceAllowConfirmedEmail = true;

There are five "triggers" on which CAPTCHAs can be displayed:

  • 'edit' - triggered on every attempted page save
  • 'create' - triggered on page creation
  • 'addurl' - triggered on a page save that would add one or more URLs to the page
  • 'createaccount' - triggered on creation of a new account
  • 'badlogin' - triggered on the next login attempt after a failed one. Requires $wgMainCacheType to be set to something other than CACHE_NONE in your LocalSettings.php, if in doubt the following will always work. Note that badlogin does not trigger captchas on API login, but instead blocks them outright until $wgCaptchaBadLoginExpiration expires.
$wgMainCacheType = CACHE_ANYTHING;

The default values for these are:

$wgCaptchaTriggers['edit']          = false; 
$wgCaptchaTriggers['create']        = false; 
$wgCaptchaTriggers['addurl']        = true; 
$wgCaptchaTriggers['createaccount'] = true;
$wgCaptchaTriggers['badlogin']      = true;

The triggers edit, create and addurl can be configured per namespace using the $wgCaptchaTriggersOnNamespace setting. If there is no $wgCaptchaTriggersOnNamespace for the current namespace, the normal $wgCaptchaTriggers apply. So suppose that in addition to the above $wgCaptchaTriggers defaults we configure the following:

$wgCaptchaTriggersOnNamespace[NS_TALK]['addurl'] = false;
$wgCaptchaTriggersOnNamespace[NS_PROJECT]['edit'] = true;

Then the CAPTCHA will not trigger when adding URLs to a talk page, but on the other hand user will need to solve a CAPTCHA any time they try to edit a page in the project namespace, even if they aren't adding a link.

URL and IP whitelists[edit]

It is possible to define a whitelist of known "good" sites for which the CAPTCHA should not kick in, when the 'addurl' action is triggered.

Sysop users can do this by editing the system message page called [[MediaWiki:Captcha-addurl-whitelist]]. The expected format is a set of regex's one per line. Comments can be added with # prefix. You can see an example of this usage on OpenStreetMap.

This set of whitelist regexes can also be defined using the $wgCaptchaWhitelist config variable in LocalSettings.php, to keep the value(s) a secret.

Some other variables you can add to LocalSettings.php:

  • $wgCaptchaWhitelistIP - List of IP ranges to allow to skip the CAPTCHA (you can also use [[MediaWiki:Captcha-ip-whitelist]]; see below for details).
  • $ceAllowConfirmedEmail - Allow users who have confirmed their e-mail addresses to post URL links

These are described more thoroughly in the code comments

[[MediaWiki:Captcha-ip-whitelist]] can be used to change the whitelisted IP addresses and IP ranges on wiki. They should be separated by newlines. If any other character (apart from a valid IP address or range) is found on a line, it will be ignored but leading and trailing whitespace characters are allowed. For example, a line with only is considered valid but # will be ignored.

Regular expressions[edit]

The global variable wgCaptchaRegexes accepts an array of regexes to be tested against the page text and will trigger the CAPTCHA in case of a match.

Wikimedia projects[edit]

For example, Wikimedia Foundation wikis use FancyCaptcha with a custom set of images and the default configuration, modified by what follows.

$wgGroupPermissions['autoconfirmed']['skipcaptcha'] = true;

This means only unregistered and newly registered users have to pass the CAPTCHA.

EmergencyCaptcha mode[edit]

Additionally the shortcut named $wmgEmergencyCaptcha is designed for use in a limited number of emergency situations, for instance in case of massive vandalism or spam attacks: it changes the default trigger values (see above) into the following:

$wgCaptchaTriggers['edit']          = true; 
$wgCaptchaTriggers['create']        = true;

So all anonymous and new users have to solve a CAPTCHA also before being able to save an edit or create a new page, in addition to the normal situation.


With Gerrit change 182551, ConfirmEdit supports rate limiting for false CAPTCHA. For more information about $wgRateLimits and how to set it up, read the manual, the action key is badcaptcha.

Test plan[edit]

See ConfirmEdit Test Plan.

Patch for even more spam protection[edit]

This is a patch to allow experienced users to bring in external links without solving a captcha, regardless if they has skipcaptcha permissions. A user is considered to be trusted if she has a large number of edits.

This patch also prohibits new users from adding _any_ external links. Such behavior should help a lot to tackle spam, because the whole reason of spam is to add such links (they call it "link building") and spam is almost always added by newly created users.


Apply the patch to extensions/ after unpacking ConfirmEdit 1.2. If you want to deviate from the defaults, add this to LocalSettings.php:

# Don't ask for a captcha for users with more than this number of edits.
$wgCaptchaTrustedThreshold = 150; // default 100
# Always reject edits adding new external links with less than this number of edits.
$wgCaptchaNewbieThreshold = 10;   // default 5

The patch isn't as well honed as it could be, for example user messages aren't localized. Also, the refusal for newbies to add external links applies no matter which permissions a user has. Other than that, it appears to work just fine. For a wiki using this patch, see http://reprap.org.

Markus "Traumflug" Hitter, September 2013, <mah@jump-ing.de>

--- ConfirmEdit/Captcha.php.2013-09-06	2013-05-28 12:10:57.000000000 -0700
+++ ConfirmEdit/Captcha.php	2013-09-08 10:30:12.000000000 -0700
@@ -1,6 +1,9 @@
 class SimpleCaptcha {
+	private $newLinks = null;
 	function getCaptcha() {
 		$a = mt_rand( 0, 100 );
 		$b = mt_rand( 0, 10 );
@@ -62,6 +65,21 @@
+	 * Insert the captcha prompt into an edit form.
+	 * @param OutputPage $out
+	 */
+	function newbieCallback( &$out ) {
+		global $wgCaptchaNewbieThreshold, $wgUser;
+		$count =  $wgUser->getEditCount();
+		$out->addWikiText( "As a spam protection measure, users with fewer than
+		                    $wgCaptchaNewbieThreshold edits are '''not''' allowed
+				    to add ''external'' links. Please use internal links
+				    instead (which is always to be perferred) or raise
+				    your edit count by doing a few edits without links.
+				    \n\nYour edit count is $count.\n\n" );
+	}
+	/**
 	 * Show a message asking the user to enter a captcha on edit
 	 * The result will be treated as wiki text
@@ -237,6 +255,34 @@
 	 * @param $editPage EditPage
 	 * @param $newtext string
+	 * @param $merged bool
+	 * @return an array with the number of newly added links
+	 */
+	function findNewLinks( &$editPage, $newtext, $merged ) {
+		if ( $this->newLinks != null )
+			return $this->newLinks;
+		if ( $merged ) {
+			// Get links from the database
+			$oldLinks = $this->getLinksFromTracker( $editPage->mArticle->getTitle() );
+			// Share a parse operation with Article::doEdit()
+			$editInfo = $editPage->mArticle->prepareTextForEdit( $newtext );
+			$newLinks = array_keys( $editInfo->output->getExternalLinks() );
+		} else {
+			// Get link changes in the slowest way known to man
+			$oldtext = $this->loadText( $editPage, $section );
+			$oldLinks = $this->findLinks( $editPage, $oldtext );
+			$newLinks = $this->findLinks( $editPage, $newtext );
+		}
+		$unknownLinks = array_filter( $newLinks, array( &$this, 'filterLink' ) );
+		$this->newLinks = array_diff( $unknownLinks, $oldLinks );
+		return $this->newLinks;
+	}
+	/**
+	 * @param $editPage EditPage
+	 * @param $newtext string
 	 * @param $section string
 	 * @param $merged bool
 	 * @return bool true if the captcha should run
@@ -246,6 +292,18 @@
 		$title = $editPage->mArticle->getTitle();
 		global $wgUser;
+		// Users with more than $wgCaptchaTrustedThreshold edits
+		// are considered to be trusted, so they don't need a captcha.
+		global $wgCaptchaTrustedThreshold;
+		if ( ! isset( $wgCaptchaTrustedThreshold ) )
+			$wgCaptchaTrustedThreshold = 100;
+		if ( $wgUser->getEditCount() > $wgCaptchaTrustedThreshold ) {
+			wfDebug( "ConfirmEdit: trusted user, skipping captcha\n" );
+			return false;
+		}
 		if ( $wgUser->isAllowed( 'skipcaptcha' ) ) {
 			wfDebug( "ConfirmEdit: user group allows skipping captcha\n" );
 			return false;
@@ -284,22 +341,7 @@
 		if ( $this->captchaTriggers( $editPage, 'addurl' ) ) {
-			// Only check edits that add URLs
-			if ( $merged ) {
-				// Get links from the database
-				$oldLinks = $this->getLinksFromTracker( $title );
-				// Share a parse operation with Article::doEdit()
-				$editInfo = $editPage->mArticle->prepareTextForEdit( $newtext );
-				$newLinks = array_keys( $editInfo->output->getExternalLinks() );
-			} else {
-				// Get link changes in the slowest way known to man
-				$oldtext = $this->loadText( $editPage, $section );
-				$oldLinks = $this->findLinks( $editPage, $oldtext );
-				$newLinks = $this->findLinks( $editPage, $newtext );
-			}
-			$unknownLinks = array_filter( $newLinks, array( &$this, 'filterLink' ) );
-			$addedLinks = array_diff( $unknownLinks, $oldLinks );
+			$addedLinks = $this->findNewLinks( $editPage, $newtext, $merged );
 			$numLinks = count( $addedLinks );
 			if ( $numLinks > 0 ) {
@@ -469,6 +511,21 @@
 			# The CAPTCHA was already checked and approved
 			return true;
+		// Always reject edits of newbies adding external links.
+		global $wgCaptchaNewbieThreshold, $wgUser;
+		if ( ! isset( $wgCaptchaNewbieThreshold ) )
+			$wgCaptchaNewbieThreshold = 5;
+		if ( $wgUser->getEditCount() < $wgCaptchaNewbieThreshold ) {
+			$addedLinks = $this->findNewLinks( $editPage, $newtext, $merged );
+			if ( count( $addedLinks ) > 0 ) {
+				wfDebug( "ConfirmEdit: rejecting newbie edit due to new links\n" );
+				$editPage->showEditForm( array( &$this, 'newbieCallback' ) );
+				return false;
+			}
+		}
 		if ( !$this->doConfirmEdit( $editPage, $newtext, $section, $merged ) ) {
 			$editPage->showEditForm( array( &$this, 'editCallback' ) );
 			return false;

Experience with this patch[edit]

After two months with this patch, we still wait for the first spam edit. Other than spambots still creating accounts, misuse of our wiki has completely disappeared.

Legitimate users apparently understand the error message. No complaints, but occasionally useless edits to raise the edit count appear. Typically, these users revert their useless edits without maintainer intervention. Exactly like planned.

-- Traumflug@reprap.org


The basic framework was designed largely by Brion Vibber, who also wrote the SimpleCaptcha and FancyCaptcha modules. The MathCaptcha module was written by Rob Church. The QuestyCaptcha module was written by Benjamin Lees. The reCAPTCHA module was written by Mike Crawford and Ben Maurer. Additional maintenance work was done by Yaron Koren.


  1. Homepage of the Asirra project
  2. MediaWiki:Questycaptchahelp-text, MediaWiki:Questycaptcha-edit, MediaWiki:Questycaptcha-addurl, MediaWiki:Questycaptcha-create and MediaWiki:Questycaptcha-createaccount.
  3. Google Blog Are you a robot? Introducing “No CAPTCHA reCAPTCHA” (December 3, 2014)

See also[edit]