Description
A heap use-after-free exists in wolfSSL's TLS 1.3 post-quantum cryptography (PQC) hybrid KeyShare processing. In the error handling path of TLSX_KeyShare_ProcessPqcHybridClient() in src/tls.c, the inner function TLSX_KeyShare_ProcessPqcClient_ex() frees a KyberKey object upon encountering an error. The caller then invokes TLSX_KeyShare_FreeAll(), which attempts to call ForceZero() on the already-freed KyberKey, resulting in writes of zero bytes over freed heap memory.
Metrics
CVSS 3.1 6.5/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:LWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| wolfSSL | wolfSSL | < 5.9.1 |
References
- https://github.com/wolfssl/wolfssl/pull/10092Issue Tracking, Patch
Timeline
- Published
- Apr 10, 2026
- Last modified
- Nov 11, 2026
- NVD status
- Analyzed