How severe is CVE-2025-11933?

CVE-2025-11933 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-11933 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-11933?

CVE-2025-11933 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-11933?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-11933 have an EU (EUVD) identifier?

Yes. CVE-2025-11933 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198525.

When was CVE-2025-11933 published?

CVE-2025-11933 was published on 2025-11-21 and last updated on 2026-06-17.

CVE-2025-11933

CVE-2025-11933 is a medium-severity vulnerability in Wolfssl with a CVSS 3.x base score of 6.5. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 2.3
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-198525
Weakness: CWE-20
Affected product: Wolfssl
Published: 2025-11-21
Last modified: 2026-06-17

Description

Improper Input Validation in the TLS 1.3 CKS extension parsing in wolfSSL 5.8.2 and earlier on multiple platforms allows a remote unauthenticated attacker to potentially cause a denial-of-service via a crafted ClientHello message with duplicate CKS extensions.

Frequently asked questions

What is CVE-2025-11933?: Improper Input Validation in the TLS 1.3 CKS extension parsing in wolfSSL 5.8.2 and earlier on multiple platforms allows a remote unauthenticated attacker to potentially cause a denial-of-service via a crafted ClientHello message with duplicate CKS extensions.
How severe is CVE-2025-11933?: CVE-2025-11933 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-11933 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-11933?: CVE-2025-11933 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-11933?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-11933 have an EU (EUVD) identifier?: Yes. CVE-2025-11933 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198525.
When was CVE-2025-11933 published?: CVE-2025-11933 was published on 2025-11-21 and last updated on 2026-06-17.

References

Affected products (1)

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

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