PYSEC-2026-2510

Vulnerability from pysec - Published: 2026-07-13 15:46 - Updated: 2026-07-13 16:04
VLAI
Details

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.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7 (High)
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
Impacted products
Name purl
hermes-agent pkg:pypi/hermes-agent
Aliases
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "hermes-agent",
        "purl": "pkg:pypi/hermes-agent"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.16.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.13.0",
        "0.14.0",
        "0.15.0",
        "0.15.1",
        "0.15.2"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-53869",
    "GHSA-4pqm-j46f-795x"
  ],
  "details": "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.",
  "id": "PYSEC-2026-2510",
  "modified": "2026-07-13T16:04:16.547323Z",
  "published": "2026-07-13T15:46:20.346348Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53869"
    },
    {
      "type": "WEB",
      "url": "https://github.com/NousResearch/hermes-agent/pull/30221"
    },
    {
      "type": "WEB",
      "url": "https://github.com/NousResearch/hermes-agent/pull/31685"
    },
    {
      "type": "WEB",
      "url": "https://github.com/NousResearch/hermes-agent/commit/d9ec90585cf7616b5972e44cf8d92bb569fc3feb"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/NousResearch/hermes-agent"
    },
    {
      "type": "WEB",
      "url": "https://github.com/NousResearch/hermes-agent/releases/tag/v2026.6.5"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/hermes-agent-dns-rebinding-bypass-via-websocket-endpoints"
    },
    {
      "type": "PACKAGE",
      "url": "https://pypi.org/project/hermes-agent"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-4pqm-j46f-795x"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Hermes Agent contains a DNS rebinding vulnerability in WebSocket endpoints that allows remote attackers to bypass Host and Origin validation"
}



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