CVE-2025-11936 Potential DoS Vulnerability through Multiple KeyShareEntry with Same Group in TLS 1.3 ClientHello

What is CVE-2025-11936?

CVE-2025-11936 is a medium-severity vulnerability in Wolfssl Wolfssl, published on 21 Nov 2025.

Official 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.

Weakness: CWE-20

Which versions are affected by CVE-2025-11936?

It affects 1 product.

Products include Wolfssl Wolfssl.

How do I fix CVE-2025-11936?

No fix has been published for CVE-2025-11936 yet. Limit exposure of the affected software until one is available.

Is CVE-2025-11936 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-11936 exists.

Other vulnerabilities in Wolfssl Wolfssl

• CVE-2024-5991 Buffer overread in domain name matching Critical 10.0
• CVE-2021-37155 Security feature bypass in n/a Critical 9.8
• CVE-2020-36177 Memory corruption in n/a Critical 9.8
• CVE-2014-2896 Memory corruption in n/a Critical 9.8
• CVE-2014-2897 Memory corruption in n/a Critical 9.8

All Wolfssl Wolfssl vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2025-11936, GHSA-2mmq-prpj-ww9q, UBUNTU-CVE-2025-11936.