CVE-2026-43820

The apple/swift-nio-ssl library is vulnerable to an out-of-bounds memory access due to improper handling of Subject Alternative Names (SANs) . The NIOSSLCertificate._subjectAlternativeNames process incorrectly assumes that all SANs are backed by an ASN1_STRING ; when processing types that are not...

CVE-2026-43820: Out-of-bounds Read

NIOSSLCertificate.subjectAlternativeNames provides access to the raw bytes for a cert's SANs. NIOSSL provides access to a buffer assumed to be backed by an ASN1STRING, but not all SANs are backed by ASN1STRING, so accessing the buffer for such a type can lead to out-of-bounds memory access. This...