CVE-2026-19600 json
Mattermost logs plaintext authentication tokens in debug-level server logs on failed auth attempts
published 2026-10-16 23 d ago modified 2026-10-27 12 d ago also EUVD-2026-102744
- cvss
- 4.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 14%
- public exploits
- 0
- none known
Summary
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
Patch / fix
- Mattermost Mattermost 11.7.11, 11.8.6, 11.9.2, 11.10.2, 11.11.0
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 23 d ago
Exploit prediction
0.24% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.5 | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N |
| NVD | 3.1 | 4.9 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N |
Affected products
- Mattermost Mattermost
Classification
- Weakness
-
- CWE-532 Insertion of Sensitive Information into Log File
References
-
mattermost.com
/security-updates
vendor-advisory
Sources
- CVE List CVE-2026-19600
- NVD CVE-2026-19600
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