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
CVSS Details
- CVSS 3.1 Base Score: 7.6
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L)
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