CVE-2024-34502

An issue was discovered in WikibaseLexeme in MediaWiki before 1.39.6, 1.40.x before 1.40.2, and 1...

9.8 CriticalFix available

An issue was discovered in WikibaseLexeme in MediaWiki before 1.39.6, 1.40.x before 1.40.2, and 1.41.x before 1.41.1. Loading Special:MergeLexemes will (attempt to) make an edit that merges the from-id to the to-id, even if the request was not a POST request, and even if it does not contain an edit token.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: High

Exploit likelihood

0.41%Up 0.4 points since May 6, 2024

What each source reports

CVE List Score used 9.8

Record: CVE-2024-34502
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-352
Updated: 2026-11-02

EUVDEUVD-2024-34831 9.8

Record: EUVD-2024-34831
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated: 2026-11-02

GitHub AdvisoriesGHSA-rq44-cfp6-2c3c 9.8

An issue was discovered in WikibaseLexeme in MediaWiki before 1.39.6, 1.40.x before 1.40.2, and 1...

Record: GHSA-rq44-cfp6-2c3c
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-352
Updated: 2026-11-02

NVD 9.8

Record: CVE-2024-34502
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-352
Updated: 2026-11-02

OSV 9.8

Record: CVE-2024-34502
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated: 2026-11-02

OSVBIT-mediawiki-2024-34502 No score

Record: BIT-mediawiki-2024-34502
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`mediawiki` Bitnami	before 1.41.1	1.41.1

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2024-34502 is a critical vulnerability (CVSS 9.8) in Mediawiki, published May 5, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.41%, the 35th percentile. Fixed in mediawiki 1.41.1.