Medium severity · published Jul 1, 2026
CVE-2026-58517
Blocked users can create and edit WikiLambda objects
4.3
CVSS
0.3%
EPSS
No
On KEV
Description
Improper neutralization of input terminators vulnerability in The Wikimedia Foundation Mediawiki - WikiLambda Extension allows Authentication Bypass.
This issue affects Mediawiki - WikiLambda Extension: from * before 1.43.9,1.44.6,1.45.4.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MW
Mediawiki - WikiLambda Extension · The Wikimedia Foundation
before 1.43.9,1.44.6,1.45.4 · source: vendor
ME
Mediawiki · Mediawiki
1.43.0 before 1.43.9; 1.44.0 before 1.44.6; 1.45.0 before 1.45.4 · source: NVD
Affected product
MW
Mediawiki - WikiLambda Extension
The Wikimedia Foundation
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-58517
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-58517
Issue Tracking
https://gerrit.wikimedia.org/r/c/1305376
Issue Tracking
https://phabricator.wikimedia.org/T428833
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