CVE-2026-9351 is a medium severity path traversal vulnerability affecting NousResearch hermes-agent versions up to 2026.4.16. The issue resides in the _is_blocked_device function within tools/file_tools.py, specifically in the read_file Tool component. An attacker can remotely manipulate file paths to traverse directories and potentially access files outside intended boundaries. The vulnerability has a CVSS 4.0 score of 6.9 with network attack vector, low attack complexity, no privileges or user interaction required, and limited impact on confidentiality and availability. The vendor has not provided a patch or official remediation, and exploit code is publicly available. The product is not cloud-hosted, so remediation is the responsibility of the user or vendor.

Successful exploitation of this vulnerability allows remote attackers to perform path traversal, potentially accessing sensitive files on the affected system. This can lead to unauthorized information disclosure or other impacts depending on the files accessed. The CVSS score of 6.9 reflects a medium severity with limited confidentiality and availability impact. No known active exploitation in the wild has been reported yet, but public exploit code availability increases the risk.

No official patch or remediation is currently available from the vendor, who has not responded to disclosure attempts. Users should monitor vendor channels for updates. Until a fix is released, consider restricting network access to the hermes-agent service to trusted sources only and applying any available application-level controls to limit file access. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.