Vulnerability Details CVE-2021-3618
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.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.004
EPSS Ranking 62.5%
CVSS Severity
CVSS v3 Score 7.4
CVSS v2 Score 5.8