nousresearch/hermes-agent · Security
Hermes Agent contains a DNS rebinding vulnerability in WebSocket endpoints that allows remote attackers to bypass Host and Origin validation
- GHSA ID
- GHSA-4pqm-j46f-795x
- CVE ID
- CVE-2026-53869
- Severity
- high
- Published
- Updated
- CVSS
- 7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS v3
- 7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS v4
- 8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Description
Hermes Agent before 0.16.0 contains a DNS rebinding vulnerability in WebSocket endpoints that allows remote attackers to bypass Host and Origin validation. FastAPI HTTP middleware does not execute for WebSocket upgrade requests on /api/pty, /api/ws, /api/pub, and /api/events endpoints, enabling attackers to exploit DNS rebinding and inject malicious commands or read terminal output.
CWEs
- CWE-306 · Missing Authentication for Critical Function
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-53869 ↗
- https://github.com/NousResearch/hermes-agent/pull/30221 ↗
- https://github.com/NousResearch/hermes-agent/pull/31685 ↗
- https://github.com/NousResearch/hermes-agent/commit/d9ec90585cf7616b5972e44cf8d92bb569fc3feb ↗
- https://github.com/NousResearch/hermes-agent/releases/tag/v2026.6.5 ↗
- https://www.vulncheck.com/advisories/hermes-agent-dns-rebinding-bypass-via-websocket-endpoints ↗
- https://github.com/advisories/GHSA-4pqm-j46f-795x ↗