CVE-2026-106498
highpriority · track · 0OT risk · elevatedEPSS 0.003 · 23 %ileUSEPSS · scored 2026-10-27
Backstage is an open framework for building developer portals. Prior to 3.5.1, 3.6.2, 3.7.2, 3.8.2 and 3.9.1, the @backstage/plugin-catalog-backend package is affected by improper url validation in catalog entity placeholder resolution. An authenticated Backstage user could craft a catalog entity with placeholder directives that reference resources outside the entity's source repository. Under certain configurations, this could allow access to data not intended to be available to the user. This issue is fixed in versions 3.5.1, 3.6.2, 3.7.2, 3.8.2 and 3.9.1.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (11)
Products and version ranges known to be affected.
- linuxfoundation backstage plugin-catalog-backend< 3.5.1nvdUScpe:2.3:a:linuxfoundation:backstage_plugin-catalog-backend:*:*:*:*:*:*:*:*
- linuxfoundation backstage plugin-catalog-backend3.6.0 → 3.6.2nvdUScpe:2.3:a:linuxfoundation:backstage_plugin-catalog-backend:*:*:*:*:*:*:*:*
- linuxfoundation backstage plugin-catalog-backend3.7.0 → 3.7.2nvdUScpe:2.3:a:linuxfoundation:backstage_plugin-catalog-backend:*:*:*:*:*:*:*:*
- linuxfoundation backstage plugin-catalog-backend3.8.0 → 3.8.2nvdUScpe:2.3:a:linuxfoundation:backstage_plugin-catalog-backend:*:*:*:*:*:*:*:*
- linuxfoundation backstage plugin-catalog-backend3.9.0 → 3.9.1nvdUScpe:2.3:a:linuxfoundation:backstage_plugin-catalog-backend:*:*:*:*:*:*:*:*
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-qgvj-qcf8-xq73Backstage: Improper URL validation in catalog entity placeholder resolution2026-10-07ghsa · osvUS
### Impact An authenticated Backstage user could craft a catalog entity with placeholder directives that reference resources outside the entity's source repository. Under certain configurations, this could allow access to data not intended to be available to the user. ### Patches Patched in `@backstage/plugin-catalog-backend` version `3.9.1` ### Workarounds If you're not able to update immediately: - Limit the scope of integration credentials (e.g., GitHub tokens) to only the repositories that Backstage needs to access.
sources
Which sources assert this record, and when.
references (11) nvd
External citations — patches, advisories, analysis.
- https://github.com/backstage/backstage/commit/0b0f6fc89b4eb4872c76a498abbe1dc65998bb6ePatch
- https://github.com/backstage/backstage/commit/286bfc1f9cc3608a073b41016be302785be385d1Patch
- https://github.com/backstage/backstage/commit/61a10f19926aeda7f4a32de48d733e6710584634Patch
- https://github.com/backstage/backstage/commit/99729e925fd2bd40ba210022351a0ee6318e6197Patch
- https://github.com/backstage/backstage/commit/e786ac309ed2d775daf2309393c015c43902d6f6Patch
- https://github.com/backstage/backstage/releases/tag/v1.49.6PatchRelease Notes
- https://github.com/backstage/backstage/releases/tag/v1.50.5PatchRelease Notes
- https://github.com/backstage/backstage/releases/tag/v1.51.3PatchRelease Notes
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