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CVE Record

CVE-2020-26120: XSS exists in the MobileFrontend extension for MediaWiki before 1.34.4 because section.line is mishandled d...

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.

UnknownCVSS not scoredNot KEV-listedUpdated
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Security readout for executives and security teams

Plain-English summary

CVE-2020-26120 is a cross-site scripting flaw in MediaWiki's MobileFrontend extension before 1.34.4. A crafted page section could make browser-side HTML parsing trigger attacker-controlled behavior. This mainly threatens wiki users and administrators who view malicious content through the mobile frontend.

Executive priority

Patch during the next normal security maintenance window, sooner for public wikis or administrator-heavy environments. No active exploitation is cited, but XSS in a content platform can affect trusted sessions and user confidence.

Technical view

The flaw is in MobileFrontend handling of section.line during regex section line replacement from PageGateway. Crafted HTML can reach jQuery parseHTML, where image callbacks may fire even without appending the element to the DOM. The source bundle names MediaWiki before 1.34.4; detailed affected package ranges are otherwise incomplete.

Likely exposure

Exposure is likely limited to MediaWiki deployments using the MobileFrontend extension before 1.34.4. Public or semi-public wikis with untrusted page edits or submitted content have higher practical risk. The bundle does not provide CPEs or complete package version ranges.

Exploitation context

The provided sources describe a crafted-HTML XSS condition but do not show CISA KEV listing or confirmed active exploitation. Treat it as potentially exploitable where attackers can place or influence wiki content viewed through MobileFrontend.

Researcher notes

Key evidence comes from the CVE description, Wikimedia Phabricator task, Gerrit fix reference, and Fedora advisory. Missing data includes CVSS, CWE, full affected CPEs, and public exploit confirmation. Avoid assuming impact beyond MobileFrontend before 1.34.4.

Mitigation direction

  • Inventory MediaWiki deployments using MobileFrontend and identify versions before 1.34.4.
  • Upgrade MediaWiki/MobileFrontend according to Wikimedia or distribution guidance.
  • Review Fedora package advisories if using Fedora-provided MediaWiki packages.
  • Restrict untrusted content editing until affected instances are updated.
  • Check vendor guidance if exact package backport status is unclear.

Validation and detection

  • Confirm whether MobileFrontend is installed and enabled on each MediaWiki instance.
  • Verify deployed MediaWiki and extension versions are not before 1.34.4.
  • Review package changelogs for the referenced Wikimedia fix identifier.
  • Search logs for suspicious edits containing crafted HTML around mobile page views.
  • Confirm security monitoring covers script execution reports or CSP violations.
Prepared
Confidence
medium
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
4Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

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