CVE-2026-106457

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{"bugzilla": {"description": "plugin-auth-backend-module-cloudflare-access-provider: Backstage: Unauthorized access via missing token audience validation", "id": "2547145", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2547145"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.8", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N", "status": "draft"}, "cwe": "CWE-303", "details": ["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.", "A flaw was found in the Backstage Cloudflare Access authentication provider module. This vulnerability allows an attacker to gain unauthorized access to the Backstage application. The provider verifies a token's signature and team issuer but fails to confirm that the token was issued for the Backstage application. Consequently, a remote attacker holding a valid token for another application within the same Cloudflare Zero Trust team can authenticate to Backstage if the request reaches the authentication endpoint without upstream audience enforcement."], "name": "CVE-2026-106457", "package_state": [{"cpe": "cpe:/a:redhat:rhdh:1", "fix_state": "Fix deferred", "package_name": "rhdh/rhdh-hub-rhel9", "product_name": "Red Hat Developer Hub"}, {"cpe": "cpe:/a:redhat:ansible_portal:2", "fix_state": "Fix deferred", "package_name": "ansible-automation-platform/bootc-automation-portal-rhel9", "product_name": "Self-service automation portal 2"}], "public_date": "2026-10-06T20:13:26Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-106457\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-106457\nhttps://github.com/backstage/backstage/commit/ed9034cacd9def3b3674f0a764fe992f751e204d\nhttps://github.com/backstage/backstage/releases/tag/v1.55.0\nhttps://github.com/backstage/backstage/security/advisories/GHSA-q333-f498-w2x7"], "threat_severity": "Moderate"}

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