CVE-2026-2645Improperly Implemented Security Check for Standard in Wolfssl

Severity
5.5MEDIUMNVD
EPSS
0.0%
top 92.01%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedMar 19

Description

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.

CVSS 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

Affected Packages5 packages

🔴Vulnerability Details

2
OSV
CVE-2026-2645: In wolfSSL 52026-03-19
GHSA
GHSA-cwc7-2fmx-fffq: In wolfSSL 52026-03-19

📋Vendor Advisories

2
Microsoft
Acceptance of CertificateVerify Message before ClientKeyExchange in TLS 1.22026-03-10
Debian
CVE-2026-2645: wolfssl - In wolfSSL 5.8.2 and earlier, a logic flaw existed in the TLS 1.2 server state m...2026

🕵️Threat Intelligence

1
Wiz
CVE-2026-2645 Impact, Exploitability, and Mitigation Steps | Wiz
CVE-2026-2645 — Wolfssl vulnerability | cvebase