Hermes Agent < 0.16.0 - DNS Rebinding Bypass via WebSocket Endpoints

{
  "id": "e1ba7e207c8e7166faa72d75caa8a386bfdc350b72ffa7ce33d679e744b93973",
  "url": "https://osv.dev/vulnerability/CVE-2026-53869",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Hermes Agent < 0.16.0 - DNS Rebinding Bypass via WebSocket Endpoints",
    "summary": "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.",
    "evidence": "osv:CVE-2026-53869",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-53869",
      "aliases": [
        "CVE-2026-53869",
        "GHSA-4pqm-j46f-795x",
        "PYSEC-2026-2510"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "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"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/nousresearch/hermes-agent",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "3c231eb3979ab9c57d5cd6d02f1d577a3b718b43"
                },
                {
                  "fixed": "d9ec90585cf7616b5972e44cf8d92bb569fc3feb"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "fixed": "3c231eb3979ab9c57d5cd6d02f1d577a3b718b43"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v2026.6.5"
                  },
                  {
                    "range": [
                      {
                        "fixed": "d9ec90585cf7616b5972e44cf8d92bb569fc3feb"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2026.5.16",
            "v2026.5.7",
            "v2026.4.30",
            "v2026.4.23",
            "v2026.4.16",
            "v2026.4.13",
            "v2026.4.8",
            "v2026.4.3",
            "v2026.3.30",
            "v2026.3.28",
            "v2026.3.23",
            "v2026.3.17",
            "v2026.3.12"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53869.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:26.214439624Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53869.json",
        "https://github.com/NousResearch/hermes-agent/releases/tag/v2026.6.5",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-53869",
        "https://www.vulncheck.com/advisories/hermes-agent-dns-rebinding-bypass-via-websocket-endpoints",
        "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"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-306"
        ],
        "cna_assigner": "VulnCheck",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "fixed": "0.16.0"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandardRange"
              }
            ]
          },
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "fixed": "0.16.0"
                  }
                ],
                "source": "DESCRIPTION"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53869.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-53869",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 492942,
  "published_at": "2026-06-17T17:57:30.978+00:00"
}