CVE-2026-53869

Hermes Agent < 0.16.0 - DNS Rebinding Bypass via WebSocket Endpoints

Published Jun 17, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-4pqm-j46f-795x Hermes Agent contains a DNS rebinding vulnerability in WebSocket endpoints that allows remote attackers to bypass Host and Origin validation
History
Type Values Removed Values Added
First Time appeared Nousresearch
Nousresearch hermes-agent
Vendors & Products Nousresearch
Nousresearch hermes-agent
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title Hermes Agent < 0.16.0 - DNS Rebinding Bypass via WebSocket Endpoints
Weaknesses CWE-306
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, 'vector': '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Nov 8, 2026, 2:05 PM
Reserved
Jun 10, 2026, 9:23 PM
Status
Deferred
Published
Jun 17, 2026, 7:18 PM
Modified
Oct 26, 2026, 11:10 AM