CVE-2026-29185: backstage Path Traversal

Vulnerability summary

CVE-2026-29185 is a low (CVSS 2.7) Path Traversal vulnerability in backstage. EPSS estimates a 0.40% chance of exploitation in the next 30 days, higher than 32.3% of scored vulnerabilities.

Timeline

1. 07-03-2026
   PublishedVulnerability first disclosed.
2. 09-03-2026
   Last modifiedVulnerability information updated.

Description

Backstage is an open framework for building developer portals. Prior to version 1.20.1, a vulnerability in the SCM URL parsing used by Backstage integrations allowed path traversal sequences in encoded form to be included in file paths. When these URLs were processed by integration functions that construct API URLs, the traversal segments could redirect requests to unintended SCM provider API endpoints using the configured server-side integration credentials. This issue has been patched in version 1.20.1.

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.