Backstage is an open framework for building developer portals. Prior to 3.9.2 and from 4.0.0 until 4.0.2, DefaultCatalogRulesEnforcer in @backstage/plugin-catalog-backend compares the raw location.target URL against catalog.rules, while URL readers canonicalize the same URL before fetching it. An authenticated user with catalog.location.create permission can use percent-encoded path segments to make an untrusted URL match a trusted location pattern even though the canonical URL resolves outside that scope. This admits entity content from an untrusted source as trusted, while further downstream consequences depend on deployment configuration. This issue is fixed in versions 3.9.2 and 4.0.2.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Mon, 26 Oct 2026 19:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Backstage
Backstage backstage |
|
| Vendors & Products |
Backstage
Backstage backstage |
Mon, 26 Oct 2026 18:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Backstage is an open framework for building developer portals. Prior to 3.9.2 and from 4.0.0 until 4.0.2, DefaultCatalogRulesEnforcer in @backstage/plugin-catalog-backend compares the raw location.target URL against catalog.rules, while URL readers canonicalize the same URL before fetching it. An authenticated user with catalog.location.create permission can use percent-encoded path segments to make an untrusted URL match a trusted location pattern even though the canonical URL resolves outside that scope. This admits entity content from an untrusted source as trusted, while further downstream consequences depend on deployment configuration. This issue is fixed in versions 3.9.2 and 4.0.2. | |
| Title | Backstage catalog rules can be bypassed for URL locations using encoded path segments | |
| Weaknesses | CWE-22 | |
| References |
|
|
| Metrics |
cvssV3_1
|
Projects
Sign in to view the affected projects.
Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-10-26T17:56:20.105Z
Reserved: 2026-10-23T20:21:45.107Z
Link: CVE-2026-115923
No data.
Status : Awaiting Analysis
Published: 2026-10-26T18:17:40.360
Modified: 2026-10-26T18:39:42.503
Link: CVE-2026-115923
No data.
OpenCVE Enrichment
Updated: 2026-10-26T19:30:15Z
Weaknesses