CVE-2026-19600
Mattermost logs plaintext authentication tokens in debug-level server logs on failed auth attempts
CVSS Score
4.5
EPSS Score
0.0%
EPSS Percentile
0th
Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to sanitize authentication tokens before writing them to server log entries, which allows an attacker with access to server logs to obtain valid session tokens or OAuth access tokens and impersonate authenticated users via the debug-level Mattermost server log.. Mattermost Advisory ID: MMSA-2026-00763
| CWE | CWE-532 |
| Vendor | mattermost |
| Product | mattermost |
| Published | Oct 16, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
High
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
Mattermost / Mattermost
11.9.0 ≤ 11.9.1 11.8.0 ≤ 11.8.5 11.7.0 ≤ 11.7.10 11.10.0 ≤ 11.10.1
Credits
CERT PL