CVE-2026-6345
CWE-522Published: May 18, 2026· Updated: May 18, 2026
Official Description
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail prevent disclosure of created user password which allows a malicious attacker to impersonate a user via the use of some of those passwords.. Mattermost Advisory ID: MMSA-2026-00614
Technical Analysis
CVE-2026-6345 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires high privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), with a CVSS base score of 6.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (1)
Quick Facts
Related CVEs (CWE-522)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-6345 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts