CVE-2026-102271

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{"bugzilla": {"description": "pyjwt: PyJWT: Authentication bypass via acceptance of DER public keys as HMAC secrets", "id": "2542687", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2542687"}, "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. The library fails to identify asymmetric public keys supplied in Distinguished Encoding Rules (DER) format, inadvertently treating the public data as a shared secret in Hash-based Message Authentication Code (HMAC) operations. If an application supports both asymmetric and symmetric signing algorithms, a remote attacker knowing the public key can exploit this flaw to forge valid authentication tokens and bypass access controls."], "name": "CVE-2026-102271", "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": "2026-09-28T20:31:53Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-102271\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-102271\nhttps://github.com/jpadilla/pyjwt/commit/2798504fa2663364573cf2d1043d8d7fef389499\nhttps://github.com/jpadilla/pyjwt/releases/tag/2.14.0\nhttps://github.com/jpadilla/pyjwt/security/advisories/GHSA-p4g4-x82p-q773"], "threat_severity": "Important"}

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