Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 Mattermost failed to restrict OAuth deauthorization and personal access token management… (CVE-2026-16045)
Mattermost versions 11.7.x up to 11.7.6 and 10.11.x up to 10.11.21 contain a vulnerability where OAuth deauthorization and personal access token management endpoints are not properly restricted to direct user sessions. This flaw allows an OAuth app with a delegated user token to revoke the user's authorizations or tokens for other integrations via account-management endpoints. The issue is tracked as CVE-2026-16045 and has a medium severity rating.
AI Analysis
Technical Summary
CVE-2026-16045 affects Mattermost versions 11.7.x <= 11.7.6 and 10.11.x <= 10.11.21. The vulnerability arises because the application fails to restrict OAuth deauthorization and personal access token management endpoints to direct user sessions. Consequently, an OAuth application possessing a delegated user token can revoke authorizations or tokens for other integrations associated with the same user account through account-management endpoints. This represents an improper authorization control issue categorized under CWE-863.
Potential Impact
An attacker controlling an OAuth app with a delegated user token can revoke the user's authorizations or personal access tokens for other integrations. This could disrupt user workflows or integrations but does not lead to confidentiality or integrity loss of data. The CVSS v3.1 score is 4.3 (medium), reflecting limited impact primarily on availability or functionality.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory (Mattermost Advisory ID: MMSA-2026-00704) for current remediation guidance. Until a fix is applied, restrict OAuth app permissions carefully and monitor for unusual token revocation activities. No official fix or patch links are currently provided in the available data.
Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 Mattermost failed to restrict OAuth deauthorization and personal access token management… (CVE-2026-16045)
Description
Mattermost versions 11.7.x up to 11.7.6 and 10.11.x up to 10.11.21 contain a vulnerability where OAuth deauthorization and personal access token management endpoints are not properly restricted to direct user sessions. This flaw allows an OAuth app with a delegated user token to revoke the user's authorizations or tokens for other integrations via account-management endpoints. The issue is tracked as CVE-2026-16045 and has a medium severity rating.
CVSS v3.1
Score 4.3medium
Affected software
pkg:github/mattermost/mattermost-serverRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16045 affects Mattermost versions 11.7.x <= 11.7.6 and 10.11.x <= 10.11.21. The vulnerability arises because the application fails to restrict OAuth deauthorization and personal access token management endpoints to direct user sessions. Consequently, an OAuth application possessing a delegated user token can revoke authorizations or tokens for other integrations associated with the same user account through account-management endpoints. This represents an improper authorization control issue categorized under CWE-863.
Potential Impact
An attacker controlling an OAuth app with a delegated user token can revoke the user's authorizations or personal access tokens for other integrations. This could disrupt user workflows or integrations but does not lead to confidentiality or integrity loss of data. The CVSS v3.1 score is 4.3 (medium), reflecting limited impact primarily on availability or functionality.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory (Mattermost Advisory ID: MMSA-2026-00704) for current remediation guidance. Until a fix is applied, restrict OAuth app permissions carefully and monitor for unusual token revocation activities. No official fix or patch links are currently provided in the available data.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-cgr5-gh7v-f893
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-16045"]
- Ecosystems
- []
- Database Specific Severity
- MODERATE
- Cvss Version
- 3.1
Threat ID: 6a833345bf8831d5392a3c6c
Added to database: 08/17/2026, 16:13:57 UTC
Last enriched: 08/17/2026, 16:16:45 UTC
Last updated: 08/17/2026, 19:01:14 UTC
Views: 3
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