How severe is CVE-2025-11936?

CVE-2025-11936 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2025-11936 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-11936?

CVE-2025-11936 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-11936?

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

Does CVE-2025-11936 have an EU (EUVD) identifier?

Yes. CVE-2025-11936 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198524.

When was CVE-2025-11936 published?

CVE-2025-11936 was published on 2025-11-21 and last updated on 2026-06-17.

CVE-2025-11936

CVE-2025-11936 is a medium-severity vulnerability in Wolfssl with a CVSS 3.x base score of 5.3. 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 5.3)
CVSS v4: 6.3
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-198524
Weakness: CWE-20
Affected product: Wolfssl
Published: 2025-11-21
Last modified: 2026-06-17

Description

Improper input validation in the TLS 1.3 KeyShareEntry parsing in wolfSSL v5.8.2 on multiple platforms allows a remote unauthenticated attacker to cause a denial-of-service by sending a crafted ClientHello message containing duplicate KeyShareEntry values for the same supported group, leading to excessive CPU and memory consumption during ClientHello processing.

Frequently asked questions

What is CVE-2025-11936?: Improper input validation in the TLS 1.3 KeyShareEntry parsing in wolfSSL v5.8.2 on multiple platforms allows a remote unauthenticated attacker to cause a denial-of-service by sending a crafted ClientHello message containing duplicate KeyShareEntry values for the same supported group, leading to excessive CPU and memory consumption during ClientHello processing.
How severe is CVE-2025-11936?: CVE-2025-11936 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2025-11936 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-11936?: CVE-2025-11936 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-11936?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-11936 have an EU (EUVD) identifier?: Yes. CVE-2025-11936 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198524.
When was CVE-2025-11936 published?: CVE-2025-11936 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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