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TI-2023-03312 Aliases CVE-2023-3550GHSA-4pqg-hr8r-h5cw

Stored XSS leads to privilege escalation in MediaWiki v1.40.0

Priority HIGH 74CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
High · High · High
Fix status
Will not fix Red Hat: no fix planned

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-79.

Summary

Mediawiki v1.40.0 does not validate namespaces used in XML files. Therefore, if the instance administrator allows XML file uploads, a remote attacker with a low-privileged user account can use this exploit to become an administrator by sending a malicious link to the instance administrator.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0138 72nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Will not fix Red Hat: no fix planned

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
mediawikiMediaWiki1.40.0—No fix listedCNA
  • MediaWiki Vendormediawiki Affected 1.40.0 Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:mediawiki:mediawiki:1.40.0:-:*:*:*:*:*:*1.40.0Vulnerablemediawiki
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*11.0VulnerableDebian
  • cpe:2.3:a:mediawiki:mediawiki:1.40.0:-:*:*:*:*:*:* Versions 1.40.0 Vulnerable ·mediawiki
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat OpenShift Container Platform 3.11AffectedNo fix planned: Out of support scope

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-3550
  2. 2026-10-03 Alias added: GHSA-4pqg-hr8r-h5cw

References

Exploit 1

Advisory 2

Other 2

  • TI-2023-18933 An issue was discovered in the CheckUser extension for MediaWiki through 1.39.3. CVSS 3.1CRITICAL 9.8
  • TI-2023-13576 An issue was discovered in MediaWiki before 1.35.10, 1.36.x through 1.38.x before 1.38.6… CVSS 3.1CRITICAL 9.8
  • TI-2026-42109 Cross-site request forgery in Wikimedia Foundation Mediawiki - RedirectManager Extension CVSS 4.0MEDIUM 6.9
  • TI-2024-22822 An issue was discovered in includes/CommentFormatter/CommentParser.php in MediaWiki… CVSS 3.1HIGH 7.4
  • TI-2023-18935 An issue was discovered in the ProofreadPage (aka Proofread Page) extension for MediaWiki… CVSS 3.1MEDIUM 5.3
  • TI-2023-18931 An issue was discovered in SubmitEntityAction in Wikibase in MediaWiki through 1.39.3. CVSS 3.1MEDIUM 5.3
See all 416 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences