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Medium · 5.0 CVE-2026-49958 EUVD-2026-35706GHSA-qg92-vxjm-x4q9

Hermes WebUI < 0.51.303 TOCTOU Race Condition via git_discard

Published Jun 9, 2026 · Updated Nov 8, 2026 · Assigned by VulnCheck

Description

Hermes WebUI before version 0.51.303 contains a time-of-check time-of-use (TOCTOU) race condition vulnerability in the git_discard function within api/workspace_git.py that allows attackers to delete files outside the configured workspace boundary by replacing a validated path component with a symlink after validation but before deletion. Attackers can substitute a workspace-controlled path component with a symlink pointing to an external directory between the safe_resolve_ws() validation step and the subsequent Path.unlink() or shutil.rmtree() deletion call, causing the delete operation to follow the symlink and remove arbitrary files outside the workspace.

Affected products

VendorProductAffectedFixed
nesquena hermes-webui < 0.51.303 0.51.303

References