Your submission was sent successfully! Close

You have successfully unsubscribed! Close

CVE-2021-3618

Published: 23 March 2022

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.

Notes

AuthorNote
mdeslaur
the mail proxy mechanisms aren't included in nginx.conf by
default

Priority

Low

Cvss 3 Severity Score

7.4

Score breakdown

Status

Package Release Status
nginx
Launchpad, Ubuntu, Debian
bionic
Released (1.14.0-0ubuntu1.10)
focal
Released (1.18.0-0ubuntu1.3)
hirsute Ignored
(reached end-of-life)
impish
Released (1.18.0-6ubuntu11.1)
jammy
Released (1.18.0-6ubuntu14.1)
kinetic Needed

trusty Needed

upstream
Released (1.21.0)
xenial
Released (1.10.3-0ubuntu0.16.04.5+esm3)
Patches:
upstream: http://hg.nginx.org/nginx/rev/ec1071830799
sendmail
Launchpad, Ubuntu, Debian
bionic Needed

focal Needed

hirsute Ignored
(reached end-of-life)
impish Ignored
(reached end-of-life)
jammy Needed

kinetic Needed

trusty Needed

upstream
Released (8.16.1-1)
xenial Needs triage

vsftpd
Launchpad, Ubuntu, Debian
bionic Needed

focal Needed

hirsute Ignored
(reached end-of-life)
impish Ignored
(reached end-of-life)
jammy Not vulnerable
(3.0.5-0ubuntu1)
kinetic Not vulnerable
(3.0.5-0ubuntu1)
trusty Needed

upstream
Released (3.0.4)
xenial Needed

Severity score breakdown

Parameter Value
Base score 7.4
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Scope Unchanged
Confidentiality High
Integrity impact High
Availability impact None
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N