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{"bugzilla": {"description": "authlib: Authlib: Authentication bypass via forged OpenID Connect ID Tokens", "id": "2448182", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2448182"}, "csaw": false, "cvss3": {"cvss3_base_score": "9.1", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "status": "draft"}, "details": ["A flaw was found in Authlib, a Python library used for building OAuth and OpenID Connect (OIDC) servers. This vulnerability allows a remote attacker to bypass critical integrity checks in OIDC ID Tokens. Specifically, the library's internal hash verification logic fails open when encountering an unsupported cryptographic algorithm, accepting a forged ID Token as valid. 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"package_name": "rhoai/odh-workbench-jupyter-tensorflow-rocm-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Affected", "package_name": "rhoai/odh-workbench-jupyter-trustyai-cpu-py312-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:quay:3", "fix_state": "Affected", "package_name": "quay/quay-rhel8", "product_name": "Red Hat Quay 3"}, {"cpe": "cpe:/a:redhat:quay:3", "fix_state": "Affected", "package_name": "quay/quay-rhel9", "product_name": "Red Hat Quay 3"}, {"cpe": "cpe:/a:redhat:satellite:6", "fix_state": "Affected", "package_name": "satellite/foreman-mcp-server-rhel9", "product_name": "Red Hat Satellite 6"}], "public_date": "2026-03-16T18:03:28Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-28498\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-28498\nhttps://github.com/authlib/authlib/commit/b9bb2b25bf8b7e01512d847a95c1749646eaa72b\nhttps://github.com/authlib/authlib/releases/tag/v1.6.9\nhttps://github.com/authlib/authlib/security/advisories/GHSA-m344-f55w-2m6j"], "statement": "This IMPORTANT vulnerability in Authlib allows attackers to bypass OIDC ID Token integrity verification. The at_hash and c_hash validation fails open for unknown algorithms, accepting forged tokens as valid. Exploitation requires no authentication or user interaction. Impact is high to confidentiality and integrity. Red Hat products using Authlib for OIDC validation are affected. Fixed in version 1.6.9.", "threat_severity": "Important"}

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