CVE-2026-106456
Backstage: Inconsistent credential enforcement for overlapping proxy routes
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.
INFO
Published Date :
Oct. 6, 2026, 9:17 p.m.
Last Modified :
Oct. 6, 2026, 9:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-106456
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update @backstage/plugin-proxy-backend to version 0.6.18.
- Review proxy route configurations for overlapping paths.
- Ensure consistent credential requirements for nested routes.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-106456.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-106456 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-106456
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-106456 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-106456 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Oct. 06, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N Added CWE CWE-863 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/106xxx/CVE-2026-106456.json">CVE-2026-106456</a> Added Reference https://github.com/backstage/backstage/commit/9df92923ac32558bb80edeceafd8de780c44e218 Added Reference https://github.com/backstage/backstage/releases/tag/v1.55.0 Added Reference https://github.com/backstage/backstage/security/advisories/GHSA-472h-9c5j-prrr