Vulnerability · Published Nov 21, 2025 · Assigned by wolfSSL
CVE-2025-11934Improper Validation of Signature Algorithm Used in TLS 1.3 CertificateVerify
Low 2.1
In plain English
A low-severity improper input validation in wolfSSL from wolfSSL. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Improper input validation in the TLS 1.3 CertificateVerify signature algorithm negotiation in wolfSSL 5.8.2 and earlier on multiple platforms allows for downgrading the signature algorithm used. For example when a client sends ECDSA P521 as the supported signature algorithm the server previously could respond as ECDSA P256 being the accepted signature algorithm and the connection would continue with using ECDSA P256, if the client supports ECDSA P256.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | wolfssl | 5.9.1-r0 | ALPINE-CVE-2025-11934 |
| Alpine:v3.24 | wolfssl | 5.8.4-r0 | ALPINE-CVE-2025-11934 |
| Debian:12 | wolfssl | no fix listed | DEBIAN-CVE-2025-11934 |
| Debian:13 | wolfssl | no fix listed | DEBIAN-CVE-2025-11934 |
| Ubuntu:22.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2025-11934 |
| Ubuntu:24.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2025-11934 |
| Ubuntu:25.10 | wolfssl | no fix listed | UBUNTU-CVE-2025-11934 |
| Ubuntu:26.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2025-11934 |
| Ubuntu:26.10 | wolfssl | no fix listed | UBUNTU-CVE-2025-11934 |
Affected products (as reported)
Weakness: CWE-20 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N