Vulnpedia
← Search CVEs

CVE-2026-106457

MEDIUM 6.8

Published 2026-10-06 · Last modified 2026-10-07

Backstage is an open framework for building developer portals. From 0.1.0 until 0.5.0, the @backstage/plugin-auth-backend-module-cloudflare-access-provider package is affected by insufficient audience validation in the cloudflare access auth provider. The Cloudflare Access auth provider verifies a token's signature and team issuer, but affected versions do not verify that the token was issued for the Backstage application. A user holding a valid token for another Access application in the same Cloudflare Zero Trust team may therefore be able to authenticate to Backstage if that token reaches the auth endpoint without the Backstage application's audience already being enforced upstream. Cloudflare Access normally evaluates the protected application before forwarding requests. This issue is fixed in version 0.5.0.

NO EXPLOITATION SIGNALS

No known exploitation, public exploit, or elevated probability at this time. Track for changes.

Exploitation likelihood

0.3%chance of exploitation in 30 days · 20th percentile

○ In CISA KEV ○ Catalogued PoC

Impact if exploited

6.8CVSS 3.1 · MEDIUM

  • ConfidentialityHigh
  • IntegrityHigh
  • AvailabilityNone

What an attacker needs

  • ✓Access: Reachable over the network — no local access needed
  • ⚠Privileges: Requires a low-privilege account
  • ✓User interaction: No user interaction needed
  • ⚠Complexity: Needs a race window or specific setup

✓ lowers the bar for an attacker · ⚠ raises it

Proof of concept

No public PoC is currently catalogued.

Search for new PoCs

Search GitHub now — results may be empty or unverified.

Tracked sources are checked daily for recent CVEs, including PoCs published after the original disclosure. A later release appears after a tracked source lists it and a refresh succeeds.

Data snapshot:

Affected

Vendors Backstage @Backstage

Products Backstage Plugin Auth Backend Module Cloudflare Access Provider

Weakness (CWE)

  • CWE-287: : Improper Authentication

CVSS vector

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

References and research data (JSON)

Packages and version ranges

Each advisory describes its own package and affected ranges. A boundary applies to that range; it is not a universal upgrade recommendation.

  • @backstage/plugin-auth-backend-module-cloudflare-access-provider npm

    pkg:npm/%40backstage/plugin-auth-backend-module-cloudflare-access-provider

    SEMVER range
    • Introduced version (included): 0.1.0
    • Fixed boundary (excluded): 0.5.0
    Additional upstream package constraints
    {
  "database": {
    "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-q333-f498-w2x7/GHSA-q333-f498-w2x7.json"
  }
}
    GitHub Advisory Database · GHSA-q333-f498-w2x7 · Updated 2026-10-07T20:30:04.832917243Z

Vendor product assessments

  • rhdh/rhdh-hub-rhel9 as a component of Red Hat Developer Hub · known affected

    Vendor assessment for this product only.

    pkg:oci/rhdh-hub-rhel9?repository_url=registry.redhat.io/rhdh/rhdh-hub-rhel9

    • none available: Fix deferred
    Red Hat · CVE-2026-106457 · Updated 2026-10-07T12:36:11+00:00
  • ansible-automation-platform/bootc-automation-portal-rhel9 as a component of Self-service automation portal 2 · known affected

    Vendor assessment for this product only.

    pkg:oci/bootc-automation-portal-rhel9?repository_url=registry.redhat.io/ansible-automation-platform/bootc-automation-portal-rhel9

    • none available: Fix deferred
    Red Hat · CVE-2026-106457 · Updated 2026-10-07T12:36:11+00:00

All CVSS metrics

  • MEDIUM 6.8 v3.1 · CNA Primary
    CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
  • MEDIUM 6.8 v3.1 · NVD Secondary
    CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

References

Advisories

Technical & other

Sources: NVD · CVE.org · EPSS