A AegiFlow
MEDIUMCVSS 4.8EPSS 0.2%

CVE-2026-106456

CVE-2026-106456 updated by NVD

Published
2026-10-07
Modified
2026-10-29
EPSS percentile
13%
Sources
github-advisory, nvd

Summary

Backstage is an open framework for building developer portals. From 0.5.0 until 0.6.18, the @backstage/plugin-proxy-backend package is affected by inconsistent credential enforcement for overlapping proxy routes. An operator can configure overlapping proxy paths with different credential requirements. When a parent path permits unauthenticated access and a nested path requires credentials, the parent exemption can also cover requests handled by the nested proxy. An unauthenticated caller may therefore reach the nested upstream through Backstage, including with static upstream credentials configured for that proxy. This issue is fixed in version 0.6.18.

Affected packages

EcosystemPackageAffected versionsFixed versions
npm@backstage/plugin-proxy-backend—0.6.18

Remediation: Upgrade to 0.6.18 or later.

References

Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

CVE® is a registered trademark of The MITRE Corporation. CVE content reproduced under the CVE Terms of Use; copyright designation © MITRE.

EPSS scores provided by the FIRST.org Exploit Prediction Scoring System.