CVE-2026-2645CWE-358

Acceptance of CertificateVerify Message before ClientKeyExchange in TLS 1.2

Medium · published March 19, 2026

CVSS v4.0
5.5
EPSS
0%
Percentile
11.3
In the wild
Unconfirmed
What it is

In wolfSSL 5.8.2 and earlier, a logic flaw existed in the TLS 1.2 server state machine implementation. The server could incorrectly accept the CertificateVerify message before the ClientKeyExchange message had been received. This issue affects wolfSSL before 5.8.4 (wolfSSL 5.8.2 and earlier is vulnerable, 5.8.4 is not vulnerable). In 5.8.4 wolfSSL would detect the issue later in the handshake. 5.9.0 was further hardened to catch the issue earlier in the handshake.

The record
Technical detail
CVSS v4.0
5.5 · MEDIUM
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P
EPSS
0.00215 · 11.3th percentile
Weakness
CWE-358 · Improperly Implemented Security Check for Standard
Published
2026-03-19T17:10Z
EPSS history
Timeline
  • 19 MAR 17:10Z
    Acceptance of CertificateVerify Message before ClientKeyExchange in TLS 1.2
    cvelistv5