CVE-2026-34086 PUBLISHED

AbuseFilter misuses ::userCanBitfield, exposing access-controlled information

Assigner: wikimedia-foundation
Reserved: 25.03.2026 Published: 11.05.2026 Updated: 11.05.2026

Vulnerability in Wikimedia Foundation AbuseFilter.

This issue affects AbuseFilter: from * before 1.43.7, 1.44.4, 1.45.2.

CVSS Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/S:N/AU:Y
CVSS Score: 2.1

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	Low	Confidentiality	Low
Attack Complexity	High	Integrity	Low	Integrity	Low
Attack Requirements	Present	Availability	None	Availability	None
Privileges Required	Low
User Interaction	Passive

CVSS 4.0

Vendor	Wikimedia Foundation
Product	AbuseFilter
Versions	Default: unaffected affected from * to 1.43.7, 1.44.4, 1.45.2 (excl.)