Low severity · published May 11, 2026
CVE-2026-34086
AbuseFilter misuses ::userCanBitfield, exposing access-controlled information
2.1
CVSS
0.2%
EPSS
No
On KEV
Description
Vulnerability in Wikimedia Foundation AbuseFilter.
This issue affects AbuseFilter: from * before 1.43.7, 1.44.4, 1.45.2.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AB
AbuseFilter · Wikimedia Foundation
before 1.43.7, 1.44.4, 1.45.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-34086
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-34086
phabricator.wikimedia.org
https://phabricator.wikimedia.org/T415584
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