CVE-2026-2645 (GCVE-0-2026-2645)

Vulnerability from cvelistv5 – Published: 2026-03-19 17:10 – Updated: 2026-03-19 17:45
VLAI?
Title
Acceptance of CertificateVerify Message before ClientKeyExchange in TLS 1.2
Summary
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.
Severity ?
5.5 (Medium)
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
CWE
  • CWE-358 - Improperly Implemented Security Check for Standard
Assigner
References
Impacted products
Vendor Product Version
wolfSSL wolfSSL Affected: 0 , < 5.8.4 (semver)
Create a notification for this product.
Date Public ?
2026-03-20 00:24
Credits
Kai Tian
Show details on NVD website
To clipboard 

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Sightings

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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