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.

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 through 1.37, the Special:ImportFile URI (aka FileImporter) allows XSS, as demonstrated by the clientUrl parameter.

In MediaWiki through 1.37, Wikibase item descriptions allow XSS, which is triggered upon a visit to an action=info URL (aka a page-information sidebar).

An issue was discovered in CentralAuth in MediaWiki through 1.36.2. The rightsnone MediaWiki message was not being properly sanitized and allowed for the injection and execution of HTML and JavaScript via the setchange log.

An issue was discovered in Special:MediaSearch in the MediaSearch extension in MediaWiki through 1.36.2. The suggestion text (a parameter to mediasearch-did-you-mean) was not being properly sanitized and allowed for the injection and execution of HTML and JavaScript via the intitle: search operator within the query.

In MediaWiki through 1.37, XSS can occur in Wikibase because an external identifier property can have a URL format that includes a $1 formatter substitution marker, and the javascript: URL scheme (among others) can be used.

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.

MediaWiki before 1.36.2 allows XSS. Month related MediaWiki messages are not escaped before being used on the Special:Search results page.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.16.4, when Internet Explorer 6 or earlier is used, allows remote attackers to inject arbitrary web script or HTML via an uploaded file accessed with a dangerous extension such as .html located before a ? (question mark) in a query string, in conjunction with a modified URI path that has a %2E sequence in place of the . (dot) character. NOTE: this vulnerability exists because of an incomplete fix for CVE-2011-1578.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.16.5, when Internet Explorer 6 or earlier is used, allows remote attackers to inject arbitrary web script or HTML via an uploaded file accessed with a dangerous extension such as .shtml at the end of the query string, in conjunction with a modified URI path that has a %2E sequence in place of the . (dot) character. NOTE: this vulnerability exists because of an incomplete fix for CVE-2011-1578 and CVE-2011-1587.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.16.3, when Internet Explorer 6 or earlier is used, allows remote attackers to inject arbitrary web script or HTML via an uploaded file accessed with a dangerous extension such as .html at the end of the query string, in conjunction with a modified URI path that has a %2E sequence in place of the . (dot) character.

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

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

Cross-site scripting (XSS) vulnerability in the Parser::replaceInternalLinks2 method in MediaWiki before 1.23.15, 1.26.x before 1.26.4, and 1.27.x before 1.27.1 allows remote attackers to inject arbitrary web script or HTML via vectors involving replacement of percent encoding in unclosed internal links.

Cross-site scripting (XSS) vulnerability in the CSS user subpage preview feature in MediaWiki before 1.23.15, 1.26.x before 1.26.4, and 1.27.x before 1.27.1 allows remote attackers to inject arbitrary web script or HTML via the edit box in Special:MyPage/common.css.

An issue was discovered in MediaWiki before 1.31.12 and 1.32.x through 1.35.x before 1.35.2. On ChangesList special pages such as Special:RecentChanges and Special:Watchlist, some of the rcfilters-filter-* label messages are output in HTML unescaped, leading to XSS.

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.

An issue was discovered in the GlobalUsage extension for MediaWiki through 1.35.1. SpecialGlobalUsage.php calls WikiMap::makeForeignLink unsafely. The $page variable within the formatItem function was not being properly escaped, allowing for XSS under certain conditions.

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.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.23.12, 1.24.x before 1.24.5, 1.25.x before 1.25.4, and 1.26.x before 1.26.1, when is configured with a relative URL, allows remote authenticated users to inject arbitrary web script or HTML via wikitext, as demonstrated by a wikilink to a page named "javascript:alert('XSS!')."

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 f parameter, which is not properly handled in an error page, related to "ForeignAPI images."

Cross-site scripting (XSS) vulnerability in the Html class 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 a LanguageConverter substitution string when using a language variant.

Cross-site scripting (XSS) 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 a custom JavaScript file, which is not properly handled when previewing the file.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.19.24, 1.2x before 1.23.9, and 1.24.x before 1.24.2, when using HHVM, allows remote attackers to inject arbitrary web script or HTML via an invalid parameter in a wddx format request to api.php, which is not properly handled in an error message, related to unsafe calls to wddx_serialize_value.

The WikibaseMediaInfo extension 1.35 for MediaWiki allows XSS because of improper template syntax within the PropertySuggestionsWidget template (in the templates/search/PropertySuggestionsWidget.mustache+dom file).

In MediaWiki before 1.35.1, the combination of Html::rawElement and Message::text leads to XSS because the definition of MediaWiki:recentchanges-legend-watchlistexpiry can be changed onwiki so that the output is raw HTML.

An issue was discovered in MediaWiki 1.32.x through 1.34.x before 1.34.4. LogEventList::getFiltersDesc is insecurely using message text to build options names for an HTML multi-select field. The relevant code should use escaped() instead of text().

Incomplete blacklist vulnerability in Sanitizer::checkCss in MediaWiki before 1.19.9, 1.20.x before 1.20.8, and 1.21.x before 1.21.3 allows remote attackers to conduct cross-site scripting (XSS) attacks via certain non-ASCII characters in CSS, as demonstrated using variations of "expression" containing (1) full width characters or (2) IPA extensions, which are converted and rendered by Internet Explorer.

Incomplete blacklist vulnerability in Sanitizer::checkCss in MediaWiki before 1.19.9, 1.20.x before 1.20.8, and 1.21.x before 1.21.3 allows remote attackers to conduct cross-site scripting (XSS) attacks via a \b (backspace) character in CSS.

The implementation of raw message parameter expansion in MediaWiki before 1.27.4, 1.28.x before 1.28.3, and 1.29.x before 1.29.2 allows HTML mangling attacks.

MediaWiki before 1.19.18, 1.20.x through 1.22.x before 1.22.9, and 1.23.x before 1.23.2 does not enforce an IFRAME protection mechanism for transcluded pages, which makes it easier for remote attackers to conduct clickjacking attacks via a crafted web site.

MediaWiki before 1.18.5, and 1.19.x before 1.19.2 does not send a restrictive X-Frame-Options HTTP header, which allows remote attackers to conduct clickjacking attacks via an embedded API response in an IFRAME element.

An issue was discovered in MediaWiki before 1.37.3 and 1.38.x before 1.38.1. The contributions-title, used on Special:Contributions, is used as page title without escaping. Hence, in a non-default configuration where a username contains HTML entities, it won't be escaped.

Cross-site scripting (XSS) vulnerability in MediaWiki 1.9.x before 1.9.2 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors related to "sortable tables JavaScript."

The FanBoxes extension for MediaWiki through 1.37.2 (before 027ffb0b9d6fe0d823810cf03f5b562a212162d4) allows Special:UserBoxes CSRF.

The Private Domains extension for MediaWiki through 1.37.2 (before 1ad65d4c1c199b375ea80988d99ab51ae068f766) allows CSRF for editing pages that store the extension's configuration. The attacker must trigger a POST request to Special:PrivateDomains.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.4.5 allows remote attackers to inject arbitrary web script via HTML attributes in page templates.

Cross-site scripting (XSS) vulnerability in includes/Sanitizer.php in the variable handler in MediaWiki 1.6.x before r14349 allows remote attackers to inject arbitrary Javascript via unspecified vectors, possibly involving the usage of the | (pipe) character.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.5.8 and 1.4.15 allows remote attackers to inject arbitrary web script or HTML via crafted encoded links.

Cross-site scripting (XSS) vulnerability in MediaWiki 1.4.6 and earlier allows remote attackers to inject arbitrary web script or HTML via a parameter to the page move template.

MediaWiki before 1.5.4 uses a hard-coded "internal placeholder string", which allows remote attackers to bypass protection against cross-site scripting (XSS) attacks and execute Javascript using inline style attributes, which are processed by Internet Explorer.

Incomplete blacklist vulnerability in MediaWiki before 1.4.11 does not properly remove certain CSS inputs (HTML inline style attributes) that are processed as active content by Internet Explorer, which allows remote attackers to conduct cross-site scripting (XSS) attacks.

Multiple cross-site scripting (XSS) vulnerabilities in MediaWiki before 1.4.9 allow remote attackers to inject arbitrary web script or HTML via (1) <math> tags or (2) Extension or <nowiki> sections that "bypass HTML style attribute restrictions" that are intended to protect against XSS vulnerabilities in Internet Explorer clients.

Cross-site scripting (XSS) vulnerability in MediaWiki before 1.4.x before 1.4.6 and 1.5 before 1.5beta3 allows remote attackers to inject arbitrary web script or HTML via a parameter in the page move template, a different vulnerability than CVE-2005-1888.