An issue was discovered in MediaWiki before 1.31.10 and 1.32.x through 1.34.x before 1.34.4. The non-jqueryMsg version of mw.message().parse() doesn't escape HTML. This affects both message contents (which are generally safe) and the parameters (which can be based on user input). (When jqueryMsg is loaded, it correctly accepts only whitelisted tags in message contents, and escapes all parameters. Situations with an unloaded jqueryMsg are rare in practice, but can for example occur for Special:SpecialPages on a wiki with no extensions installed.)

An issue was discovered in MediaWiki 1.34.x before 1.34.4. On Special:Contributions, the NS filter uses unescaped messages as keys in the option key for an HTMLForm specifier. This is vulnerable to a mild XSS if one of those messages is changed to include raw HTML.

In MediaWiki before 1.31.10 and 1.32.x through 1.34.x before 1.34.4, XSS related to jQuery can occur. The attacker creates a message with [javascript:payload xss] and turns it into a jQuery object with mw.message().parse(). The expected result is that the jQuery object does not contain an <a> tag (or it does not have a href attribute, or it's empty, etc.). The actual result is that the object contains an <a href ="javascript... that executes when clicked.

Cross-site scripting (XSS) vulnerability in the Special:Block implementation in the getContribsLink function in SpecialBlockip.php in MediaWiki 1.14.0 and 1.15.0 allows remote attackers to inject arbitrary web script or HTML via the ip parameter.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.16.2 allows remote attackers to inject arbitrary web script or HTML via crafted Cascading Style Sheets (CSS) comments, aka "CSS injection vulnerability."

Cross-site scripting (XSS) vulnerability in MediaWiki 1.15 before 1.15.4 and 1.16 before 1.16 beta 3 allows remote attackers to inject arbitrary web script or HTML via crafted Cascading Style Sheets (CSS) strings that are processed as script by Internet Explorer.

MediaWiki before 1.27.4, 1.28.x before 1.28.3, and 1.29.x before 1.29.2 has XSS when the $wgShowExceptionDetails setting is false and the browser sends non-standard URL escaping.

Cross-site scripting (XSS) vulnerability in contrib/cssgen.php in the GeSHi, as used in the SyntaxHighlight_GeSHi extension and MediaWiki before 1.23.10, 1.24.x before 1.24.3, and 1.25.x before 1.25.2, allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

MediaWiki before 1.19.24, 1.2x before 1.23.9, and 1.24.x before 1.24.2 does not properly handle when the Zend interpreter xml_parse function does not expand entities, which allows remote attackers to inject arbitrary web script or HTML via a crafted SVG file.

Cross-site scripting (XSS) vulnerability in thumb.php in MediaWiki before 1.23.10, 1.24.x before 1.24.3, and 1.25.x before 1.25.2 allows remote attackers to inject arbitrary web script or HTML via the rel404 parameter, which is not properly handled in an error page.

The VisualEditor extension through 1.34 for MediaWiki allows XSS via pasted content containing an element with a data-ve-clipboard-key attribute.

Incomplete blacklist vulnerability in includes/upload/UploadBase.php in MediaWiki before 1.19.24, 1.2x before 1.23.9, and 1.24.x before 1.24.2 allows remote attackers to inject arbitrary web script or HTML via an application/xml MIME type for a nested SVG with a data: URI.

Cross-site scripting (XSS) vulnerability in the Scribunto extension for MediaWiki allows remote attackers to inject arbitrary web script or HTML via a function name, which is not properly handled in a Lua error backtrace.

ShortDescription is a MediaWiki extension that provides local short description support. A cross-site scripting (XSS) vulnerability exists in versions prior to 2.3.4. On a wiki that has the ShortDescription enabled, XSS can be triggered on any page or the page with the action=info parameter, which displays the shortdesc property. This is achieved using the wikitext `{{SHORTDESC:&lt;img src=x onerror=alert()&gt;}}`. This issue has a patch in version 2.3.4.

Cross-site scripting (XSS) vulnerability in MediaWiki 1.13.1, 1.12.0, and possibly other versions before 1.13.2 allows remote attackers to inject arbitrary web script or HTML via the useskin parameter to an unspecified component.

Cross-site scripting (XSS) vulnerability in the preview in the TemplateSandbox extension for MediaWiki allows remote attackers to inject arbitrary web script or HTML via the text parameter to Special:TemplateSandbox.

Multiple cross-site scripting (XSS) vulnerabilities in the Listings extension for MediaWiki allow remote attackers to inject arbitrary web script or HTML via the (1) name or (2) url parameter.

Cross-site scripting (XSS) vulnerability in the Hovercards extension for MediaWiki allows remote attackers to inject arbitrary web script or HTML via vectors related to text extracts.

In the MobileFrontend extension 1.31 through 1.33 for MediaWiki, XSS exists within the edit summary field in includes/specials/MobileSpecialPageFeed.php.

In the MobileFrontend extension for MediaWiki, XSS exists within the edit summary field of the watchlist feed. This affects REL1_31, REL1_32, and REL1_33.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.19.19, 1.22.x before 1.22.11, and 1.23.x before 1.23.4 allows remote attackers to inject arbitrary web script or HTML via a crafted SVG file.

Wikimedia MediaWiki 1.30.0 through 1.32.1 has XSS. Loading user JavaScript from a non-existent account allows anyone to create the account, and perform XSS on users loading that script. Fixed in 1.32.2, 1.31.2, 1.30.2 and 1.27.6.

includes/upload/UploadBase.php in MediaWiki before 1.19.12, 1.20.x and 1.21.x before 1.21.6, and 1.22.x before 1.22.3 does not prevent use of invalid namespaces in SVG files, which allows remote attackers to conduct cross-site scripting (XSS) attacks via an SVG upload, as demonstrated by use of a W3C XHTML namespace in conjunction with an IFRAME element.

Cross-site scripting (XSS) vulnerability in includes/actions/InfoAction.php in MediaWiki before 1.21.9 and 1.22.x before 1.22.6 allows remote attackers to inject arbitrary web script or HTML via the sort key in an info action.

Cross-site scripting (XSS) vulnerability in the formatHTML function in includes/api/ApiFormatBase.php in MediaWiki before 1.19.12, 1.20.x and 1.21.x before 1.21.6, and 1.22.x before 1.22.3 allows remote attackers to inject arbitrary web script or HTML via a crafted string located after http:// in the text parameter to api.php.

Cross-site scripting (XSS) vulnerability in MediaWiki 1.13.0 through 1.13.2 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Incomplete blacklist vulnerability in MediaWiki before 1.19.24, 1.2x before 1.23.9, and 1.24.x before 1.24.2 allows remote attackers to inject arbitrary web script or HTML via an animated href XLink element.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.19.10, 1.2x before 1.21.4, and 1.22.x before 1.22.1 allows remote attackers to inject arbitrary web script or HTML via a -o-link attribute.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.19.10, 1.2x before 1.21.4, and 1.22.x before 1.22.1 allows remote attackers to inject arbitrary web script or HTML via crafted XSL in an SVG file.

Cross-site scripting (XSS) vulnerability in MediaWiki 1.19.9 before 1.19.10, 1.2x before 1.21.4, and 1.22.x before 1.22.1 allows remote attackers to inject arbitrary web script or HTML via unspecified CSS values.

Cross-site scripting (XSS) vulnerability in the TimeMediaHandler extension for MediaWiki before 1.19.10, 1.2x before 1.21.4, and 1.22.x before 1.22.1 allows remote attackers to inject arbitrary web script or HTML via vectors related to videos.

Cross-site scripting (XSS) vulnerability in pages/TalkpageHistoryView.php in the LiquidThreads (LQT) extension 2.x and possibly 3.x for MediaWiki 1.19.x before 1.19.8, 1.20.x before 1.20.7, and 1.21.x before 1.21.2 allows remote attackers to inject arbitrary web script or HTML via a thread subject.

Cross-site scripting (XSS) vulnerability in contrib/example.php in the SyntaxHighlight GeSHi extension for MediaWiki, possibly as downloaded before September 2013, allows remote attackers to inject arbitrary web script or HTML via the PATH_INFO.

Multiple cross-site scripting (XSS) vulnerabilities in repo/includes/EntityView.php in the Wikibase extension for MediaWiki 1.19.x before 1.19.8, 1.20.x before 1.20.7, and 1.21.x before 1.21.2 allow (1) remote attackers to inject arbitrary web script or HTML via a label in the "In other languages" section or (2) remote administrators to inject arbitrary web script or HTML via a description.

A cross-site scripting (XSS) vulnerability in MediaWiki before 1.19.5 and 1.20.x before 1.20.4 and allows remote attackers to inject arbitrary web script or HTML via Lua function names.

Cross-site scripting (XSS) vulnerability in mediawiki.page.image.pagination.js in MediaWiki 1.22.x before 1.22.9 and 1.23.x before 1.23.2 allows remote attackers to inject arbitrary web script or HTML via vectors involving the multipageimagenavbox class in conjunction with an action=raw value.

Cross-site scripting (XSS) vulnerability in the RSS Reader extension before 0.2.6 for MediaWiki allows remote attackers to inject arbitrary web script or HTML via a crafted feed.

Multiple cross-site scripting (XSS) vulnerabilities in MediaWiki before 1.18.5 and 1.19.x before 1.19.2, when unspecified JavaScript gadgets are used, allow remote attackers to inject arbitrary web script or HTML via the userlang parameter to w/index.php.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.18.5 and 1.19.x before 1.19.2 allows remote attackers to inject arbitrary web script or HTML via a File: link to a nonexistent image.

Cross-site scripting (XSS) vulnerability in the outputPage function in includes/SkinTemplate.php in MediaWiki before 1.17.5, 1.18.x before 1.18.4, and 1.19.x before 1.19.1 allows remote attackers to inject arbitrary web script or HTML via the uselang parameter to index.php/Main_page.

The MinervaNeue Skin in MediaWiki from 2019-11-05 to 2019-12-13 (1.35 and/or 1.34) mishandles certain HTML attributes, as demonstrated by IMG onmouseover= (impact is XSS) and IMG src=http (impact is disclosing the client's IP address). This can occur within a talk page topical header that is viewed within a mobile (MobileFrontend) context.

An issue was discovered in MediaWiki before 1.35.7, 1.36.x and 1.37.x before 1.37.3, and 1.38.x before 1.38.1. XSS can occur in configurations that allow a JavaScript payload in a username. After account creation, when it sets the page title to "Welcome" followed by the username, the username is not escaped: SpecialCreateAccount::successfulAction() calls ::showSuccessPage() with a message as second parameter, and OutputPage::setPageTitle() uses text().

Cross-site scripting (XSS) vulnerability in the BotQuery extension in MediaWiki 1.7.x and earlier before SVN 20070910 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors, a similar issue to CVE-2007-4828.

Cross-site scripting (XSS) vulnerability in the API pretty-printing mode in MediaWiki 1.8.0 through 1.8.4, 1.9.0 through 1.9.3, 1.10.0 through 1.10.1, and the 1.11 development versions before 1.11.0 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

The RSS extension before 2022-04-29 for MediaWiki allows XSS via an rss element (if the feed is in $wgRSSUrlWhitelist and $wgRSSAllowLinkTag is true).

An XSS issue was discovered in MediaWiki before 1.35.6, 1.36.x before 1.36.4, and 1.37.x before 1.37.2. The widthheight, widthheightpage, and nbytes properties of messages are not escaped when used in galleries or Special:RevisionDelete.