CVE-2026-6961: Path traversal via unsanitized FileInfo.Name in Mattermost federation sync
Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to sanitize FileInfo.Name received from federated peers during shared channel file sync, which allows an attacker who controls a federated server to write files to arbitrary locations within the target server's filestore via path traversal sequences in the filename field.. Mattermost Advisory ID: MMSA-2026-00661
Problem Types
| Type | CWE ID | Description |
|---|
| CWE | CWE-22 | CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') |
Type: CWE
Description: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Metrics
| Version | Base score | Base severity | Vector |
|---|
| 3.1 | 7.6 | HIGH | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L |
Version: 3.1
Base score: 7.6
Base severity: HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L