CVE-2026-93851 json
Path traversal in Mattermost Agents plugin mention reminder allows plugin replacement via crafted post
published 2026-10-28 11 d ago modified 2026-10-30 9 d ago also EUVD-2026-112505
- cvss
- 8.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 18%
- 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 fail to validate the target post ID in the Agents plugin's mention reminder component, which allows an authenticated user who can post in a channel visible to a system administrator to cause the administrator's browser to send an unintended API request, resulting in replacement of an installed plugin and code execution on the server, via a crafted post containing a forged mention reminder that the administrator clicks. Mattermost Advisory ID: MMSA-2026-00742
Patch / fix
- Mattermost Mattermost 11.7.11, 11.8.6, 11.9.2, 11.10.0
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 11 d ago
Exploit prediction
0.27% chance of exploitation in the next 30 days, higher than 18% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.0 | CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H |
Affected products
- Mattermost Mattermost
Classification
- Weakness
-
- CWE-22 Improper Limitation of a Pathname to a Restricted Directory
References
-
mattermost.com
/security-updates
vendor-advisory
Sources
- CVE List CVE-2026-93851
- NVD CVE-2026-93851
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