Komari Allows Cross-site WebSocket Hijacking

{
  "id": "7b7e610ce71790532cb08b32193912f6994f91d69240ccc0d9ded0b618865a31",
  "url": "https://osv.dev/vulnerability/CVE-2025-55300",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Komari Allows Cross-site WebSocket Hijacking",
    "summary": "Komari is a lightweight, self-hosted server monitoring tool designed to provide a simple and efficient solution for monitoring server performance. Prior to 1.0.4-fix1, WebSocket upgrader has disabled origin checking, enabling Cross-Site WebSocket Hijacking (CSWSH) attacks against authenticated users. Any third party website can send requests to the terminal websocket endpoint with browser's cookies, resulting in remote code execution. This vulnerability is fixed in 1.0.4-fix1.",
    "evidence": "osv:CVE-2025-55300",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2025-55300",
      "aliases": [
        "CVE-2025-55300",
        "GHSA-q355-h244-969h",
        "GO-2025-3874"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/komari-monitor/komari",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "d31d12e59febce100ab0285b93338f09aa5d6cb1"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.0.4-fix1"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "d31d12e59febce100ab0285b93338f09aa5d6cb1"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.0.4-fix1"
                      }
                    ],
                    "source": "DESCRIPTION"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.0.4",
            "1.0.3-fix1",
            "1.0.1",
            "1.0.0",
            "0.1.6-fix1",
            "0.1.6",
            "0.1.5-fix1",
            "0.1.5",
            "0.1.5-pre1",
            "0.1.4",
            "0.1.3",
            "0.1.2-fix3",
            "0.1.2-fix2",
            "0.1.2-fix1",
            "0.1.2",
            "0.1.1",
            "0.1.0-fix1",
            "0.1.0",
            "0.1.0-pre3",
            "0.1.0-pre2",
            "0.1.0-prerelease",
            "0.0.9",
            "0.0.8",
            "0.0.7",
            "0.0.6",
            "0.0.5a",
            "0.0.5",
            "0.0.4",
            "0.0.3"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-55300.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:38.183289587Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/55xxx/CVE-2025-55300.json",
        "https://github.com/komari-monitor/komari/security/advisories/GHSA-q355-h244-969h",
        "https://nvd.nist.gov/vuln/detail/CVE-2025-55300",
        "https://github.com/komari-monitor/komari/commit/d31d12e59febce100ab0285b93338f09aa5d6cb1"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/55xxx/CVE-2025-55300.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2025-55300",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 505660,
  "published_at": "2025-08-18T17:41:37.372+00:00"
}