CVE-2026-106456
MEDIUM
MEDIUM
Priority: 0.02
BB Relevance:
73/100
Published: 2026-10-06
Modified: 2026-10-27
First seen: 2026-10-29
Status: active
Attack Surface
Network
Low Complexity
No Auth
No Interaction
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
None
S:
Unchanged
C:
Low
I:
Low
A:
None
Description
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.
Weakness Classification (1)
Affected Software (2)
| Vendor | Product | Version |
|---|---|---|
| linuxfoundation | backstage | 1.28.0 – 1.55.0 |
| linuxfoundation | backstage\/plugin-proxy-backend | 0.5.0 – 0.6.18 |
References & Advisories (3)
Patch
Release Notes
Patch
Mitigation
Vendor Advisory