CVE-2026-4646 (GCVE-0-2026-4646)

Vulnerability from cvelistv5 – Published: 2026-05-22 10:25 – Updated: 2026-05-22 12:13
VLAI
Title
Insufficient input validation in GitHub plugin API causes denial of service
Summary
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-22 12:13 UTC
CWE
  • CWE-1287 - Improper Validation of Specified Type of Input
Assigner
Mattermost CNA under the mitre root
CNA scorecard B 80/100 over 122 records in the last 180 days details
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version CPE status
Mattermost Mattermost Affected: 11.6.0 , ≤ 11.6.0 (semver)
Affected: 11.5.0 , ≤ 11.5.3 (semver)
Affected: 11.4.0 , ≤ 11.4.4 (semver)
Affected: 10.11.0 , ≤ 10.11.14 (semver)
Unaffected: 11.7.0
Unaffected: 11.6.1
Unaffected: 11.5.4
Unaffected: 11.4.5
Unaffected: 10.11.15
guessed Create a notification for this product.
Show details on NVD website

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