CVE-2026-106489Published

Backstage: Improper authorization enforcement for TechDocs static content

Collected exploitation and prediction evidence

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

cve-program · CVE-2026-106489

Published

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.

Source published: 6 Oct 2026 20:39:50 UTC
Source modified: 7 Oct 2026 15:29:13 UTC
Observed here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

euvd · EUVD-2026-94008

Published

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Oct 6, 2026, 8:39:50 PM

dateUpdated: Oct 7, 2026, 3:29:13 PM

Source published: Oct 6, 2026, 8:39:50 PM (timezone not stated)
Source modified: Oct 7, 2026, 3:29:13 PM (timezone not stated)
Observed here: 7 Nov 2026 04:30:27 UTC
Source terms: ENISA EUVD · source terms and attribution apply

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

nvd · CVE-2026-106489

Published

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Analyzed

Weakness classifications: CWE-22 · CWE-862

Original publisher date fields

published: 2026-10-06T21:17:17.770

lastModified: 2026-10-22T14:42:34.903

2 source CPE criteria · context only

cpe:2.3:a:linuxfoundation:backstage\/plugin-techdocs-backend:*:*:*:*:*:node.js:*:*
cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*

The original JSON retains the logical configuration operators, exclusions and version bounds.

Source published: 6 Oct 2026 21:17:17 UTC
Source modified: 22 Oct 2026 14:42:34 UTC
Observed here: 25 Oct 2026 04:17:41 UTC
Source terms: NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

osv · GHSA-rg9r-hr7g-5gc2

Published

### 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.

Source published: 7 Oct 2026 18:00:06 UTC
Source modified: 7 Oct 2026 18:15:13 UTC
Observed here: 24 Oct 2026 13:17:17 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Publisher rating · MODERATE