CVE-2021-3618

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.

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.45%
Third-Party Advisory alpaca-attack.com Third-Party Advisory redhat.com Third-Party Advisory debian.org
Affected: n/a ALPACA
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1975623 issue tracking third party advisory patch
https://alpaca-attack.com/ third party advisory
https://lists.debian.org/debian-lts-announce/2022/11/msg00031.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-3618?
CVE-2021-3618 has been scored as a high severity vulnerability.
How to fix CVE-2021-3618?
To fix CVE-2021-3618, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-3618 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-3618 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3618?
CVE-2021-3618 affects n/a ALPACA.
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