CVE-2021-3618
nginx - security update
7.4
HIGH
CVSS 3.1
EPSS 0.61%
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.
How to fix CVE-2021-3618
To remediate CVE-2021-3618, upgrade the affected package to a fixed version below.
- —upgrade to 1.20.1-r1 or later
- —upgrade to 1.21.0 or later
- —upgrade to 1.21.0 or later
- —upgrade to 1.14.2-2+deb10u5 or later
- —upgrade to 1.18.0-6.1+deb11u2 or later
- —no fix listed
- —no fix listed
Is CVE-2021-3618 being exploited?
Low — EPSS is 0.6%, meaning exploitation activity has not been observed at scale.
Affected packages (7)
- from 0, < 1.20.1-r1
- from 0, < 1.21.0
- from 0, < 1.21.0
- from 0, < 1.14.2-2+deb10u5
- from 0, < 1.18.0-6.1+deb11u2
- from 0
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.4 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N |