{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "0.0.51"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "DESCRIPTION"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "f30668f65075c93440bd59ce2de73ce9e78751f4"
            }
          ],
          "repo": "https://github.com/oasdiff/oasdiff-action",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-fhj3-7267-7vv5"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-1188",
      "CWE-200",
      "CWE-918"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53507.json"
  },
  "details": "oasdiff-action is a GitHub Action that detects breaking changes in OpenAPI specs and post a review on every pull request. Before version 0.0.51, the oasdiff actions resolved external $refs in the OpenAPI spec by default (allow-external-refs: true). When an action runs on a pull request whose spec is attacker-controlled — most importantly fork pull requests on public repositories — a $ref in that spec is fetched/read on the runner with no interaction required, enabling SSRF and disclosure of structured files on the runner. This issue has been patched in version 0.0.51.",
  "id": "CVE-2026-53507",
  "modified": "2026-09-03T03:30:38.175364943Z",
  "published": "2026-08-31T18:57:41.097Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53507.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/oasdiff/oasdiff-action/security/advisories/GHSA-fhj3-7267-7vv5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53507"
    },
    {
      "type": "FIX",
      "url": "https://github.com/oasdiff/oasdiff-action/pull/128"
    },
    {
      "type": "FIX",
      "url": "https://github.com/oasdiff/oasdiff-action/pull/129"
    },
    {
      "type": "FIX",
      "url": "https://github.com/oasdiff/oasdiff-action/pull/130"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "oasdiff actions resolve external $refs by default, enabling SSRF and disclosure of structured files on pull-request runs"
}