Sceawere

Vulnerability Detail

CVE-2026-18551 Verified Sceawere Triage Sources: NVD / CISA KEV

Vulnerability Metadata

Severity
Medium
Score / CVSS
6.5
Creation Date
3h ago
Vendor
Mattermost
Product
Mattermost
Attack Type
CWE-863: Incorrect Authorization
Vector String
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Attack Complexity
LOW

Narrative and Response

Description

Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to validate the combination of guest and admin scheme roles which allows an authenticated attacker to escalate a guest account to team or channel admin via a crafted PUT request to the member roles API endpoint.. Mattermost Advisory ID: MMSA-2026-00752

Executive Summary

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Executive Summary Locked

Sign up to unlock professional threat analysis, mitigations, and indicator signatures.

Technical Details

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Detailed Technical Analysis Locked

Sign up to unlock professional threat analysis, mitigations, and indicator signatures.

Mitigations

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Remediation & Mitigations Locked

Sign up to unlock professional threat analysis, mitigations, and indicator signatures.

References

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Intelligence References Locked

Sign up to unlock professional threat analysis, mitigations, and indicator signatures.

Additional Metadata

{
  "score": "6.5",
  "pubDate": "2026-10-16T07:17:12.260Z",
  "pubdate": "2026-10-16T07:17:12.260Z"
}
CVE-2026-18551: CVE-2026-18551 Vulnerability (MEDIUM Severity, CVSS: 6.5) | Sceawere