Vulnerability · Published Oct 6, 2026 · Assigned by GitHub_M
CVE-2026-106458Backstage: Inconsistent repository filtering in Bitbucket Server catalog event updates
Medium 6.5
In plain English
A medium-severity incorrect authorization in backstage from backstage. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 19% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Backstage is an open framework for building developer portals. From 0.4.0 until 0.5.15, the @backstage/plugin-catalog-backend-module-bitbucket-server package is affected by inconsistent repository filtering in bitbucket server catalog event updates. Deployments using event-driven updates in the Bitbucket Server catalog provider may ingest catalog locations from repositories that are excluded by the provider's configured project, repository, or archived-repository filters. An authenticated Bitbucket Server user who can push to a filtered-out repository that remains readable by the configured Backstage integration can trigger a legitimate repository event. The affected event path may then add a Location for that repository even though scheduled discovery excludes it. This issue is fixed in version 0.5.15.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @backstage/plugin-catalog-backend-module-bitbucket-server | 0.5.15 | GHSA-c36c-cf6r-ghgj |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| backstage | backstage | >= 1.38.0, < 1.55.0 |
| @backstage | plugin-catalog-backend-module-bitbucket-server | >= 0.4.0, < 0.5.15 |
Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N