CVE-2026-93851
Path traversal in Mattermost Agents plugin mention reminder allows plugin replacement via crafted post
CVSS Score
8.0
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 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
| CWE | CWE-22 |
| Vendor | mattermost |
| Product | mattermost |
| Published | Oct 28, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
Required
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
Mattermost / Mattermost
11.9.0 ≤ 11.9.1 11.8.0 ≤ 11.8.5 11.7.0 ≤ 11.7.10
Credits
z01dberg