CVE-2026-11310
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk4th percentile — higher than 4% of all known CVEs
Summary
The vulnerability allows bypassing X.509 trust-chain validation in the wolfSSL_X509_verify_cert() function of the wolfSSL library. It only affects builds with --enable-opensslextra (OPENSSL_EXTRA) and applications that call X509_verify_cert() with caller-supplied untrusted intermediate certificates. An attacker can present a chain that never reaches a configured trust anchor and have it accepted, resulting in acceptance of an attacker-controlled certificate.
Risk Assessment
The risk involves accepting a fraudulent certificate in non-TLS scenarios such as S/MIME, CMS, code/firmware signing, or JWT/JWS with x5c. This could lead to compromise of data or code integrity and authenticity.
Recommendation
It is recommended to immediately update the wolfSSL library to a patched version. If updating is not possible, avoid using the X509_verify_cert() function with untrusted intermediate certificates or disable the --enable-opensslextra option.
Original NVD description (English source)
X.509 trust-chain bypass in the OpenSSL compatibility certificate verifier (wolfSSL_X509_verify_cert()). This affects only builds with --enable-opensslextra (OPENSSL_EXTRA) and whose application validates certificates by calling X509_verify_cert() with caller-supplied untrusted intermediate certificates; for those users it is critical, otherwise the library is unaffected. In particular, native wolfSSL TLS/DTLS usage is not impacted. wolfSSL's X509_verify_cert() temporarily loads each caller-supplied untrusted intermediate into the certificate manager but failed to drop them before the trusted-store check, so an untrusted intermediate could anchor the path itself. An attacker can present a chain that never reaches a configured trust anchor and have it accepted, resulting in acceptance of an attacker-controlled certificate. This is certificate verification independent of TLS (e.g. S/MIME/CMS, code/firmware signing, JWT/JWS x5c), is not specific to any key type or algorithm, and a single untrusted intermediate suffices. The default wolfSSL TLS handshake (WOLFSSL_VERIFY_PEER) is not affected; only TLS applications doing manual or deferred peer verification through this API are, which also requires --enable-sessioncerts.