{"id":"BIT-nginx-2021-3618","details":"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.","aliases":["BIT-nginx-gateway-2021-3618","CVE-2021-3618"],"modified":"2026-09-08T08:48:16.855662913Z","published":"2024-03-06T10:59:22.065Z","database_specific":{"severity":"High","cpes":["cpe:2.3:a:f5:nginx:*:*:*:*:*:*:*:*"]},"references":[{"type":"ADVISORY","url":"https://alpaca-attack.com/"},{"type":"ADVISORY","url":"https://bugzilla.redhat.com/show_bug.cgi?id=1975623"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2022/11/msg00031.html"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-3618"}],"affected":[{"package":{"name":"nginx","ecosystem":"Bitnami","purl":"pkg:bitnami/nginx"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.21.0"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/nginx/BIT-nginx-2021-3618.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"}]}],"schema_version":"1.9.0"}