description: ALPACA is an application layer protocol content confusion attack, exploiting TLS servers implementing different protocols but using compatible certificates, such as multi-domain or wildcard certificates. A MiTM attacker having access to victim's traffic at the TCP/IP layer can redirect traffic from one subdomain to another, resulting in a valid TLS session. This breaks the authentication of TLS and cross-protocol attacks may be possible where the behavior of one protocol service may compromise the other at the application layer.
problem types: CWE-295
affected:
{
vendor: n/a
product: ALPACA
versions:
version: vsftpd 3.0.4, nginx 1.21.0, sendmail 8.17, status: affected
}