Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-2645— Acceptance of CertificateVerify Message before ClientKeyExchange in TLS 1.2

Quick assessment

Affected
wolfSSL wolfSSL
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

wolfSSL（CyaSSL）是美国wolfSSL公司的一个针对嵌入式系统开发人员使用的小的、可移植的嵌入式SSL编程库。 wolfSSL（CyaSSL） 5.8.4之前版本存在安全漏洞，该漏洞源于TLS 1.2服务器状态机实现存在逻辑缺陷，可能导致服务器在收到ClientKeyExchange消息之前错误地接受CertificateVerify消息。

AI Predicted 5.9 Difficulty: Theoretical EPSS 0.21% · P10
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-2645

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Acceptance of CertificateVerify Message before ClientKeyExchange in TLS 1.2
Source: CVE Program / CVE List V5
Vulnerability 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.
Source: CVE Program / CVE List V5
CVSS Information
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
Source: CVE Program / CVE List V5
Vulnerability Type
不恰当实现的标准安全检查
Source: CVE Program / CVE List V5
Vulnerability Title
wolfSSL（CyaSSL） 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
wolfSSL（CyaSSL）是美国wolfSSL公司的一个针对嵌入式系统开发人员使用的小的、可移植的嵌入式SSL编程库。 wolfSSL（CyaSSL） 5.8.4之前版本存在安全漏洞，该漏洞源于TLS 1.2服务器状态机实现存在逻辑缺陷，可能导致服务器在收到ClientKeyExchange消息之前错误地接受CertificateVerify消息。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
wolfSSL wolfSSL 0 ~ 5.8.4 -

II. Public POCs for CVE-2026-2645

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-2645

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-2645 (1)

Same Patch Batch · wolfSSL · 2026-03-19 · 11 CVEs total

CVE-2026-3547 7.5 HIGH wolfSSL: out-of-bounds read (DoS) in ALPN parsing due to incomplete validation
CVE-2026-0819 Stack buffer overflow in PKCS7 SignedData encoding with custom signed attributes
CVE-2026-1005 Integer underflow leads to out-of-bounds access in sniffer AES-GCM/CCM/ARIA-GCM decrypt pa
CVE-2026-2646 Heap buffer overflow in session parsing with wolfSSL_d2i_SSL_SESSION() function
CVE-2026-3548 Buffer overflow in CRL number parsing in wolfSSL
CVE-2026-3579 Non-constant time multiplication subroutine __muldi3 on RISC-V RV32I
CVE-2026-3580 Compiler-induced timing leak in sp_256_get_entry_256_9 on RISC-V
CVE-2026-4395 Heap-based buffer overflow in wc_ecc_import_x963_ex KCAPI path
CVE-2026-3230 Improper key_share validation in TLS 1.3 HelloRetryRequest
CVE-2026-4159 wc_PKCS7_DecodeEnvelopedData 1 byte out-of-bounds read

IV. Related Vulnerabilities

Same product: wolfSSL
Same vendor: wolfSSL
Same weakness: CWE-358

V. Comments for CVE-2026-2645

No comments yet

Leave a comment