CVE-2026-102266

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{"bugzilla": {"description": "pyjwt: pyjwt: Authentication bypass via empty HMAC key acceptance", "id": "2542671", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2542671"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.4", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N", "status": "draft"}, "cwe": "CWE-347", "details": ["A flaw was found in pyjwt. A remote attacker can forge authentication tokens and bypass security controls by signing tokens with an empty key. When verifying tokens against a JSON Web Key (JWK) set that contains an empty Hash-based Message Authentication Code (HMAC) key, the library fails to enforce key-length validation. This allows an attacker to generate valid tokens carrying arbitrary claims to gain unauthorized access."], "name": "CVE-2026-102266", "package_state": [{"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "package_name": "jaeger", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "package_name": "llvm21", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "package_name": "rust", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "package_name": "swift-lang", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-09-28T20:21:26Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-102266\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-102266\nhttps://github.com/jpadilla/pyjwt/commit/f91ed44dd65baaf457f4b3353ed35e98a753934c\nhttps://github.com/jpadilla/pyjwt/releases/tag/2.14.0\nhttps://github.com/jpadilla/pyjwt/security/advisories/GHSA-9j54-fg26-wv3r"], "threat_severity": "Important"}

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