CVE-2026-6330 | The ML-KEM ARM64 NEON ciphertext comparison only compares ha… | CVSS 6.3 MEDIUM

Description

The ML-KEM ARM64 NEON ciphertext comparison only compares half of the input, breaking the Fujisaki-Okamoto transform's implicit rejection and weakening IND-CCA2 security on that code path. The constant-time comparison effectively ignored part of the re-encrypted ciphertext, so a decapsulating party could fail to detect a manipulated ciphertext and proceed without the standard's required implicit rejection.

Metadata

CVE ID: CVE-2026-6330
State: PUBLISHED
Assigner: wolfSSL
Reserved: 2026-04-15 03:08 UTC
Published: 2026-06-25 21:01 UTC
Last updated: 2026-06-25 21:01 UTC
Primary CWE: CWE-327
CWE-327 Use of a Broken or Risky Cryptographic Algorithm
Vendor / Product: wolfSSL / wolfSSL
Sources: cve.org · NVD

Severity & Metrics

6.3 MEDIUM CVSS 4.0

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Affected products (1)

Vendor	Product	Platform	Versions
wolfSSL	wolfSSL	—	5.7.4 ≤ 5.9.1

Weakness (CWE)

CWE	Source	Description
CWE-327	cna	CWE-327 Use of a Broken or Risky Cryptographic Algorithm

CVSS scores (1)

Score	Severity	Version	Source	Vector
6.3	MEDIUM	4.0	cna	CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

References (2)