CVE-2026-6957
Path traversal in Mattermost Legal Hold plugin via unsanitized file name from federated peer allows arbitrary file write.
CVSS Score
8.0
EPSS Score
0.0%
EPSS Percentile
0th
Mattermost Plugins versions <=1.1.5 fail to sanitize filenames received from federated peers before using them to construct export destination paths, which allows an administrator of a remote federated Mattermost server to write files to arbitrary locations within the target server's filestore via a malicious filename delivered through the shared-channel attachment sync protocol. Mattermost Advisory ID: MMSA-2026-00659
| CWE | CWE-22 |
| Vendor | mattermost |
| Product | mattermost |
| Published | May 27, 2026 |
| Last Updated | May 28, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
High
Privileges Required
High
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
Mattermost / Mattermost
0 ≤ 1.1.5
Credits
Hassan Mohammed