CVE-2026-74889

openssl_encrypt before 1.4.0 Weak Key Derivation via HKDF

9.3 CriticalFix available

openssl_encrypt versions before 1.4.0 use HKDF with no salt and static info parameter in key normalization functions, reducing entropy extraction and determinism. Attackers can exploit predictable key derivation with identical inputs to weaken cryptographic security against multi-target attacks.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: High

Exploit likelihood

0.35%Up 0.1 points since Aug 18, 2026

What each source reports

CVE List Score used 9.3

openssl_encrypt before 1.4.0 Weak Key Derivation via HKDF

Record: CVE-2026-74889
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-326
Updated: 2026-11-02

EUVDEUVD-2026-60108 9.3

Record: EUVD-2026-60108
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Updated: 2026-11-02

GitHub AdvisoriesGHSA-fxcp-mjj5-v58w 9.3

openssl_encrypt versions before 1.4.0 use HKDF with no salt and static info parameter in key...

Record: GHSA-fxcp-mjj5-v58w
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-326
Updated: 2026-11-02

NVD 9.3

Record: CVE-2026-74889
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-326
Updated: 2026-11-02

OSV 9.3

openssl_encrypt before 1.4.0 Weak Key Derivation via HKDF

Record: CVE-2026-74889
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weakness: CWE-326
Updated: 2026-11-02

OSVPYSEC-2026-3765 9.3

Record: PYSEC-2026-3765
CVSS 4.0: 9.3 CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Updated: 2026-11-02

Affected products

jahlives openssl encrypt

Affected packages

Affected packages
Package	Affected	Fixed
`openssl-encrypt` PyPI	before 1.4.0, plus listed versions 0.2.20.2.30.2.40.2.50.2.6 Show 39 moreShow less 0.3.00.3.10.3.20.3.30.4.00.4.10.4.20.4.30.4.40.5.00.5.10.5.30.6.0rc10.7.0rc20.7.10.7.20.8.00.8.10.8.20.9.21.0.01.0.11.0.21.0.31.1.01.2.01.2.11.3.01.3.11.3.21.3.31.3.41.3.51.4.0b31.4.0b41.4.0b51.4.0b61.4.0b71.4.0b8	1.4.0

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-74889 is a critical vulnerability (CVSS 9.3) in Jahlives Openssl Encrypt, published August 17, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.35%, the 28th percentile. Fixed in openssl-encrypt 1.4.0.