CVE-2026-4646
Insufficient input validation in GitHub plugin API causes denial of service
Published: May 22, 2026Updated: May 22, 2026 Sources: CVE List BDUCWE-1287CWE-1287: Improper Validation of Specified Type of Input
4.3CVSSMEDIUM
Description
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate user-supplied input in API request handlers which allows an authenticated attacker to crash the plugin process via a crafted HTTP request to the PR details endpoint.. Mattermost Advisory ID: MMSA-2026-00638
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:LPrivileges RequiredLow
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:NIntegrityNone
A:LAvailabilityLow
Weaknesses
Affected Products
Exploitability
Official Patch Available
References
Timeline
Published
May 22, 2026
Last Updated
May 22, 2026
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