{"id":"PYSEC-2026-3976","details":"openssl_encrypt versions before 1.4.6 contain a key derivation flaw in sequential XOR composition mode where the last stage cancels out during key generation. When configured with a single KDF and no prior hashing stage, attackers can bypass memory-hard key derivation and perform offline password cracking at SHA-256 speed instead of the configured KDF cost.","aliases":["CVE-2026-74871","GHSA-vxf9-vwp6-2w43"],"modified":"2026-09-11T11:00:06.684184126Z","published":"2026-08-17T11:16:41.427Z","references":[{"type":"ADVISORY","url":"https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-vxf9-vwp6-2w43"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/openssl-encrypt-before-kdf-bypass-via-sequential-xor"}],"affected":[{"package":{"name":"openssl-encrypt","ecosystem":"PyPI","purl":"pkg:pypi/openssl-encrypt"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.6"}]}],"versions":["0.2.2","0.2.3","0.2.4","0.2.5","0.2.6","0.3.0","0.3.1","0.3.2","0.3.3","0.4.0","0.4.1","0.4.2","0.4.3","0.4.4","0.5.0","0.5.1","0.5.3","0.6.0rc1","0.7.0rc2","0.7.1","0.7.2","0.8.0","0.8.1","0.8.2","0.9.2","1.0.0","1.0.1","1.0.2","1.0.3","1.1.0","1.2.0","1.2.1","1.3.0","1.3.1","1.3.2","1.3.3","1.3.4","1.3.5","1.4.0","1.4.0b3","1.4.0b4","1.4.0b5","1.4.0b6","1.4.0b7","1.4.0b8","1.4.1","1.4.1rc2","1.4.2","1.4.4","1.4.5"],"ecosystem_specific":{},"database_specific":{"source":"https://github.com/pypa/advisory-database/blob/main/vulns/openssl-encrypt/PYSEC-2026-3976.yaml"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"}]}