CVE-2026-53869

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/NousResearch/hermes-agent/commit/d9ec90585cf7616b5972e44cf8d92bb569fc3feb
https://github.com/NousResearch/hermes-agent/pull/30221
https://github.com/NousResearch/hermes-agent/pull/31685
https://github.com/NousResearch/hermes-agent/releases/tag/v2026.6.5
https://www.vulncheck.com/advisories/hermes-agent-dns-rebinding-bypass-via-websocket-endpoints

Configurations

No configuration.

History

18 Jun 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-17 19:18

Updated : 2026-06-18 17:16

NVD link : CVE-2026-53869

Mitre link : CVE-2026-53869

CVE.ORG link : CVE-2026-53869

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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