Riskcovery

CVE-2026-106491

Backstage: Improper input validation in proxy-backend

State
Published
Severity
6.4 Medium
Published
Oct 6, 2026
Updated
Oct 7, 2026
Reserved
Oct 6, 2026

Read the record on cve.org

Description

Backstage is an open framework for building developer portals. Prior to 0.6.17, the @backstage/plugin-proxy-backend package is affected by improper input validation in proxy-backend. An authenticated Backstage user could craft a request URL that causes the proxy-backend to forward the request to a path outside the configured base path on the target server. This is limited to target servers already configured as proxy endpoints and requires Backstage authentication by default. This issue is fixed in version 0.6.17.

Scores

CVSSScoreVectorSource
3.16.4 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:NGitHub_M

Weaknesses

  • CWE-20 Improper Input Validation
  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Affected Products

ProductVersions
backstagebackstage
  • < 1.54.6Affected
plugin-proxy-backend@backstage
  • < 0.6.17Affected

References

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