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.
History

Mon, 17 Aug 2026 11:15:00 +0000

Type Values Removed Values Added
Description 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.
Title openssl_encrypt before 1.4.6 KDF Bypass via Sequential-XOR
Weaknesses CWE-916
References
Metrics cvssV3_1

{'score': 6.2, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}

cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-08-17T17:35:33.166Z

Reserved: 2026-08-17T10:31:04.593Z

Link: CVE-2026-74871

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-17T11:16:41.427

Modified: 2026-08-17T18:18:15.477

Link: CVE-2026-74871

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-17T12:45:03Z