How severe is CVE-2026-2645?

CVE-2026-2645 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2026-2645 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-2645?

CVE-2026-2645 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-2645?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-2645 have an EU (EUVD) identifier?

Yes. CVE-2026-2645 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-13135.

When was CVE-2026-2645 published?

CVE-2026-2645 was published on 2026-03-19 and last updated on 2026-06-17.

CVE-2026-2645

CVE-2026-2645 is a high-severity vulnerability in Wolfssl with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-358.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 5.5
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-13135
Weakness: CWE-358
Affected product: Wolfssl
Published: 2026-03-19
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-2645?: 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.
How severe is CVE-2026-2645?: CVE-2026-2645 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2026-2645 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-2645?: CVE-2026-2645 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-2645?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-2645 have an EU (EUVD) identifier?: Yes. CVE-2026-2645 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-13135.
When was CVE-2026-2645 published?: CVE-2026-2645 was published on 2026-03-19 and last updated on 2026-06-17.

References

https://github.com/wolfSSL/wolfssl/pull/9694

Affected products (1)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

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