Vulnerability · Published Jun 25, 2026 · Assigned by wolfSSL
CVE-2026-6330ML-KEM ARM64 NEON ciphertext comparison only compares half of the input
Medium 6.3
In plain English
A medium-severity broken cryptography in wolfSSL from wolfSSL. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.24 | wolfssl | 5.9.2-r0 | ALPINE-CVE-2026-6330 |
| Debian:12 | wolfssl | no fix listed | DEBIAN-CVE-2026-6330 |
| Debian:13 | wolfssl | no fix listed | DEBIAN-CVE-2026-6330 |
| Ubuntu:22.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2026-6330 |
| Ubuntu:24.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2026-6330 |
| Ubuntu:25.10 | wolfssl | no fix listed | UBUNTU-CVE-2026-6330 |
| Ubuntu:26.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2026-6330 |
| Ubuntu:26.10 | wolfssl | no fix listed | UBUNTU-CVE-2026-6330 |
Affected products (as reported)
Weakness: CWE-327 · Vector: 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