Riskcovery

CVE-2026-53507

oasdiff actions resolve external $refs by default, enabling SSRF and disclosure of structured files on pull-request runs

State
Published
Severity
8.3 High
Published
Aug 31, 2026
Updated
Sep 1, 2026
Reserved
Jun 9, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
4.08.3 HighCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:NGitHub_M

Weaknesses

  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-918 Server-Side Request Forgery (SSRF)
  • CWE-1188 Insecure Default Initialization of Resource

Affected Products

ProductVersions
oasdiff-actionoasdiff
  • < 0.0.51Affected

References

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