HIGH 8.0 Go
Mattermost has a Path Traversal issue
GHSA-c4r7-j7pp-r8mp · CVE-2026-4858 · GO-2026-5311
Published · Modified
Description
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to check integration URL for path traversal which allows an malicious authenticated user to call an arbitrary API via system admin Mattermost auth token using via path traversal in integration action URL. Mattermost Advisory ID: MMSA-2026-00640.
References
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