CVE-2026-53507

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/oasdiff/oasdiff-action/pull/128
https://github.com/oasdiff/oasdiff-action/pull/129
https://github.com/oasdiff/oasdiff-action/pull/130
https://github.com/oasdiff/oasdiff-action/security/advisories/GHSA-fhj3-7267-7vv5

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-31 19:16

Updated : 2026-09-09 21:09

NVD link : CVE-2026-53507

Mitre link : CVE-2026-53507

CVE.ORG link : CVE-2026-53507

JSON object : View

Products Affected

No product.

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

CWE-918

Server-Side Request Forgery (SSRF)

CWE-1188

Initialization of a Resource with an Insecure Default

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