Mediawiki Cross-site Scripting

An issue was discovered in SecurePoll in the Growth extension in MediaWiki through 1.36.2. Simple polls allow users to create alerts by changing their User-Agent HTTP header and submitting a vote. (2022-09-29, CVE-2021-42045)

An issue was discovered in the GlobalWatchlist extension in MediaWiki through 1.36.2. The rev-deleted-user and ntimes messages were not properly escaped and allowed for users to inject HTML and JavaScript. (2022-09-29, CVE-2021-42046)

An issue was discovered in the Growth extension in MediaWiki through 1.36.2. Any admin can add arbitrary JavaScript code to the Newcomer home page footer, which can be executed by viewers with zero edits. (2022-09-29, CVE-2021-42048)

An issue was discovered in the Growth extension in MediaWiki through 1.36.2. On any Wiki with the Mentor Dashboard feature enabled, users can login with a mentor account and trigger an XSS payload (such as alert) via Growthexperiments-mentor-dashboard-mentee-overview-no-js-fallback. (2022-09-29, CVE-2021-42047)

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(). (2022-07-02, CVE-2022-34911)

The Nimbus skin for MediaWiki through 1.37.2 (before 6f9c8fb868345701d9544a54d9752515aace39df) allows XSS in Advertise link messages. (2022-04-29, CVE-2022-29907)

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. (2022-03-30, CVE-2022-28202)

An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. Special:CheckUserLog allows CheckUser XSS because of date mishandling, as demonstrated by an XSS payload in MediaWiki:October. (2022-01-10, CVE-2021-46150)

An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. The WikibaseMediaInfo component is vulnerable to XSS via the caption fields for a given media file. (2022-01-10, CVE-2021-46146)

In MediaWiki through 1.37, the Special:ImportFile URI (aka FileImporter) allows XSS, as demonstrated by the clientUrl parameter. (2021-12-24, CVE-2021-45474)

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). (2021-12-24, CVE-2021-45473)

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. (2021-12-24, CVE-2021-45472)

MediaWiki before 1.36.2 allows XSS. Month related MediaWiki messages are not escaped before being used on the Special:Search results page. (2021-10-11, CVE-2021-41798)

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. (2021-10-06, CVE-2021-42041)

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. (2021-10-06, CVE-2021-42043)

An issue was discovered in SpecialEditGrowthConfig in the GrowthExperiments extension in MediaWiki through 1.36.2. The growthexperiments-edit-config-error-invalid-title MediaWiki message was not being properly sanitized and allowed for the injection and execution of HTML and JavaScript. (2021-10-06, CVE-2021-42042)

An issue was discovered in the Mentor dashboard in the GrowthExperiments extension in MediaWiki through 1.36.2. The Growthexperiments-mentor-dashboard-mentee-overview-add-filter-total-edits-headline, growthexperiments-mentor-dashboard-mentee-overview-add-filter-starred-headline, growthexperiments-mentor-dashboard-mentee-overview-info-text, growthexperiments-mentor-dashboard-mentee-overview-info-legend-headline, and growthexperiments-mentor-dashboard-mentee-overview-active-ago MediaWiki messages were not being properly sanitized and allowed for the injection and execution of HTML and JavaScript. (2021-10-06, CVE-2021-42044)

An XSS issue was discovered in the SocialProfile extension in MediaWiki through 1.36. Within several gift-related special pages, a privileged user with the awardmanage right could inject arbitrary HTML and JavaScript within various gift-related data fields. The attack could easily propagate across many pages for many users. (2021-07-02, CVE-2021-36130)

An XSS issue was discovered in the SportsTeams extension in MediaWiki through 1.36. Within several special pages, a privileged user could inject arbitrary HTML and JavaScript within various data fields. The attack could easily propagate across many pages for many users. (2021-07-02, CVE-2021-36131)

An issue was discovered in the CommentBox extension for MediaWiki through 1.35.2. Via crafted configuration variables, a malicious actor could introduce XSS payloads into various layers. (2021-04-22, CVE-2021-31550)

An issue was discovered in the PageForms extension for MediaWiki through 1.35.2. Crafted payloads for Token-related query parameters allowed for XSS on certain PageForms-managed MediaWiki pages. (2021-04-22, CVE-2021-31551)

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. (2021-04-06, CVE-2021-30157)

An issue was discovered in MediaWiki before 1.31.12 and 1.32.x through 1.35.x before 1.35.2. On Special:NewFiles, all the mediastatistics-header-* messages are output in HTML unescaped, leading to XSS. (2021-04-06, CVE-2021-30154)

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. (2020-12-21, CVE-2020-35622)

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. (2020-12-18, CVE-2020-35474)

In MediaWiki before 1.35.1, the messages userrights-expiry-current and userrights-expiry-none can contain raw HTML. XSS can happen when a user visits Special:UserRights but does not have rights to change all userrights, and the table on the left side has unchangeable groups in it. (The right column with the changeable groups is not affected and is escaped correctly.) (2020-12-18, CVE-2020-35475)

MediaWiki before 1.35.1 allows XSS via BlockLogFormatter.php. Language::translateBlockExpiry itself does not escape in all code paths. For example, the return of Language::userTimeAndDate is is always unsafe for HTML in a month value. This affects MediaWiki 1.12.0 and later. (2020-12-18, CVE-2020-35479)

MediaWiki before 1.35.1 allows XSS via BlockLogFormatter.php. MediaWiki:blanknamespace potentially can be output as raw HTML with SCRIPT tags via LogFormatter::makePageLink(). This affects MediaWiki 1.33.0 and later. (2020-12-18, CVE-2020-35478)

includes/CologneBlueTemplate.php in the CologneBlue skin for MediaWiki through 1.35 allows XSS via a qbfind message supplied by an administrator. (2020-11-24, CVE-2020-29002)

The PollNY extension for MediaWiki through 1.35 allows XSS via an answer option for a poll question, entered during Special:CreatePoll or Special:UpdatePoll. (2020-11-24, CVE-2020-29003)

The RandomGameUnit extension for MediaWiki through 1.35 was not properly escaping various title-related data. When certain varieties of games were created within MediaWiki, their names or titles could be manipulated to generate stored XSS within the RandomGameUnit extension. (2020-10-28, CVE-2020-27957)

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(). (2020-09-27, CVE-2020-25815)

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. (2020-09-27, CVE-2020-25812)

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.) (2020-09-27, CVE-2020-25828)

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 tag (or it does not have a href attribute, or it's empty, etc.). The actual result is that the object contains an CVE-2020-25814)

XSS exists in the MobileFrontend extension for MediaWiki before 1.34.4 because section.line is mishandled during regex section line replacement from PageGateway. Using crafted HTML, an attacker can elicit an XSS attack via jQuery's parseHTML method, which can cause image callbacks to fire even without the element being appended to the DOM. (2020-09-27, CVE-2020-26120)

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). (2020-01-08, CVE-2020-6163)

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. (2019-12-19, CVE-2019-19910)

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. (2019-07-10, CVE-2019-12471)

Cross site scripting is an attack where a web page executes code that is injected by an adversary. It usually appears, when users input is presented. This attack can be used to impersonate a user, take over control of the session, or even steal API keys.

The attack can be executed e.g. when you application injects the request parameter directly into the HTML code of the page returned to the user:

https://server.com/confirmation?message=Transaction+Complete

what results in:

<span>Confirmation: Transaction Complete</span>

In that case the message can be modified to become a valid Javascript code, e.g.:

https://server.com/confirmation?message=<script>dangerous javascript code here</script>

and it will be executed locally by the user's browser with full access to the user's personal application/browser data:

<span>Confirmation: <script>dangerous javascript code here</script></span>