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 victims 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.
The product does not validate, or incorrectly validates, a certificate.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Nginx | F5 | * | 1.21.0 (excluding) |