CVE-2026-6829: nesquena hermes-webui Arbitrary Workspace Directory Access

Vulnerability summary

CVE-2026-6829 is a medium (CVSS 6.3) Path Traversal vulnerability in nesquena hermes-webui. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 30.8% of scored vulnerabilities.

Timeline

1. 21-04-2026
   PublishedVulnerability first disclosed.
2. 14-07-2026
   Last modifiedVulnerability information updated.

Description

nesquena hermes-webui contains a trust-boundary failure vulnerability that allows authenticated attackers to set or change a session workspace to an arbitrary existing directory on disk by manipulating workspace path parameters in endpoints such as /api/session/new, /api/session/update, /api/chat/start, and /api/workspaces/add. Attackers can repoint a session workspace to a directory outside the intended trusted root and then use ordinary file read and write APIs to access or modify files outside the intended workspace boundary within the permissions of the hermes-webui process.

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.