Improper Certificate Signature Verification in X.509 Chain Validation Allows Forged Leaf Certificates
概要
Improper Certificate Signature Verification in X.509 Chain Validation Allows Forged Leaf Certificates
原文の説明
取得元が公開している説明をそのまま載せています (多くは英語)。
wolfSSL_X509_verify_cert in the OpenSSL compatibility layer accepts a certificate chain in which the leaf's signature is not checked, if the attacker supplies an untrusted intermediate with Basic Constraints CA:FALSE that is legitimately signed by a trusted root. An attacker who obtains any leaf certificate from a trusted CA (e.g. a free DV cert from Let's Encrypt) can forge a certificate for any subject name with any public key and arbitrary signature bytes, and the function returns WOLFSSL_SUCCESS / X509_V_OK. The native wolfSSL TLS handshake path (ProcessPeerCerts) is not susceptible and the issue is limited to applications using the OpenSSL compatibility API directly, which would include integrations of wolfSSL into nginx and haproxy.
ディストリビューション別の修正状況
各ディストリビューションが公開している、この CVE の修正パッケージ
- Debian DEBIAN-CVE-2026-5501 wolfssl
- Ubuntu UBUNTU-CVE-2026-5501 wolfssl
参照URL
- advisory github.com
- advisory nvd.nist.gov
- patch github.com