CVE-2026-106489
Backstage: Improper authorization enforcement for TechDocs static content
Backstage is an open framework for building developer portals. Prior to 2.2.4, the @backstage/plugin-techdocs-backend package is affected by improper authorization enforcement for techdocs static content. An authenticated user with access to one TechDocs documentation site could craft a URL able to read documentation belonging to a different entity. This only affects deployments using the external TechDocs builder with an external storage provider (S3, GCS, etc.) and the permission framework enabled. Instances that do not use the permission framework are unaffected, since TechDocs content is visible to all authenticated users by design. This issue is fixed in version 2.2.4.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Backstage: Improper authorization enforcement for TechDocs static content
Backstage is an open framework for building developer portals. Prior to 2.2.4, the @backstage/plugin-techdocs-backend package is affected by improper authorization enforcement for techdocs static content. An authenticated user with access to one TechDocs documentation site could craft a URL able to read documentation belonging to a different entity. This only affects deployments using the external TechDocs builder with an external storage provider (S3, GCS, etc.) and the permission framework enabled. Instances that do not use the permission framework are unaffected, since TechDocs content is visible to all authenticated users by design. This issue is fixed in version 2.2.4.
- Record
CVE-2026-106489- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-22, CWE-862
- Updated
- 2026-11-02
EUVDEUVD-2026-94008
Backstage is an open framework for building developer portals. Prior to 2.2.4, the @backstage/plugin-techdocs-backend package is affected by improper authorization enforcement for techdocs static content. An authenticated user with access to one TechDocs documentation site could craft a URL able to read documentation belonging to a different entity. This only affects deployments using the external TechDocs builder with an external storage provider (S3, GCS, etc.) and the permission framework enabled. Instances that do not use the permission framework are unaffected, since TechDocs content is visible to all authenticated users by design. This issue is fixed in version 2.2.4.
- Record
EUVD-2026-94008- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-rg9r-hr7g-5gc2
Backstage: Improper authorization enforcement for TechDocs static content
Impact
An authenticated user with access to one TechDocs documentation site could craft a URL able to read documentation belonging to a different entity. This only affects deployments using the external TechDocs builder with an external storage provider (S3, GCS, etc.) and the permission framework enabled. Instances that do not use the permission framework are unaffected, since TechDocs content is visible to all authenticated users by design.
Patches
Patched in @backstage/plugin-techdocs-backend version 2.2.4
Workarounds
- None other than upgrading. Deployments that serve TechDocs from local storage are not affected.
- Record
GHSA-rg9r-hr7g-5gc2- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-22, CWE-862
- Updated
- 2026-11-02
NVD
Backstage is an open framework for building developer portals. Prior to 2.2.4, the @backstage/plugin-techdocs-backend package is affected by improper authorization enforcement for techdocs static content. An authenticated user with access to one TechDocs documentation site could craft a URL able to read documentation belonging to a different entity. This only affects deployments using the external TechDocs builder with an external storage provider (S3, GCS, etc.) and the permission framework enabled. Instances that do not use the permission framework are unaffected, since TechDocs content is visible to all authenticated users by design. This issue is fixed in version 2.2.4.
- Record
CVE-2026-106489- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-22, CWE-862
- Updated
- 2026-11-02
OSV
Backstage: Improper authorization enforcement for TechDocs static content
Backstage is an open framework for building developer portals. Prior to 2.2.4, the @backstage/plugin-techdocs-backend package is affected by improper authorization enforcement for techdocs static content. An authenticated user with access to one TechDocs documentation site could craft a URL able to read documentation belonging to a different entity. This only affects deployments using the external TechDocs builder with an external storage provider (S3, GCS, etc.) and the permission framework enabled. Instances that do not use the permission framework are unaffected, since TechDocs content is visible to all authenticated users by design. This issue is fixed in version 2.2.4.
- Record
CVE-2026-106489- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-22, CWE-862
- Updated
- 2026-11-02
OSVGHSA-rg9r-hr7g-5gc2
Backstage: Improper authorization enforcement for TechDocs static content
Impact
An authenticated user with access to one TechDocs documentation site could craft a URL able to read documentation belonging to a different entity. This only affects deployments using the external TechDocs builder with an external storage provider (S3, GCS, etc.) and the permission framework enabled. Instances that do not use the permission framework are unaffected, since TechDocs content is visible to all authenticated users by design.
Patches
Patched in @backstage/plugin-techdocs-backend version 2.2.4
Workarounds
- None other than upgrading. Deployments that serve TechDocs from local storage are not affected.
- Record
GHSA-rg9r-hr7g-5gc2- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-22, CWE-862
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@backstage/plugin-techdocs-backendnpm |
before 2.2.4 | 2.2.4 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-106489 is a medium vulnerability (CVSS 6.5) in @backstage Plugin-techdocs-backend, published October 6, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.29%, the 21st percentile. Fixed in @backstage/plugin-techdocs-backend 2.2.4.
References
github.com/backstage/backstage/security/advisories/GHSA-rg9r-hr7g-5gc2
nvd.nist.gov/vuln/detail/CVE-2026-106489