CVE-2026-2645Acceptance of CertificateVerify Message before ClientKeyExchange in TLS 1.2
- 5.5MediumCVSS base score
- 0.14%Exploitation in 30 daysEPSS · top 97% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By wolfSSL
- 30 days later
· 30 days later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| wolfSSLCNA (assigner) | 4.0 | Medium5.5 | 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 |
| NVDNVD · Analyzed | 4.0 | Medium5.5 | 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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.14% · top 97% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-13135 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-2645)Record last updated .