CVE-2025-8023: Mattermost Fails to Sanitize Path Traversal Sequences

August 21, 2025 (updated August 29, 2025)

Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.9.x <= 10.9.2 fails to sanitize path traversal sequences in template file destination paths, which allows a system admin to perform path traversal attacks via malicious path components, potentially enabling malicious file placement outside intended directories.

References

github.com/advisories/GHSA-x67c-v8jr-p29r
github.com/mattermost/mattermost
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2025-8023
pkg.go.dev/vuln/GO-2025-3907

Code Behaviors & Features

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