{"id":"CVE-2026-53507","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-53507","summary":"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…","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.","published":"2026-08-31T19:16:49.867","modified":"2026-08-31T19:16:49.867","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/oasdiff/oasdiff-action/pull/128","label":"oasdiff/oasdiff-action#128"},"references":[{"type":"WEB","url":"https://github.com/oasdiff/oasdiff-action/pull/128"},{"type":"WEB","url":"https://github.com/oasdiff/oasdiff-action/pull/129"},{"type":"WEB","url":"https://github.com/oasdiff/oasdiff-action/pull/130"},{"type":"WEB","url":"https://github.com/oasdiff/oasdiff-action/security/advisories/GHSA-fhj3-7267-7vv5"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-08-31T19:16:49.867"}}