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CVE-2021-3618

Published: Mar 23, 2022Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-295
NVD MITRE
7.4CVSSHIGH
EPSS Score
2.0%
Top 21.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

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.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:HI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-295

Affected Products

ALPACAn/a
nginxf5
On-premWeb App
Networking Infrastructure / load-balancer-proxy
sendmailsendmail
On-prem
Communications / email-server-client
vsftpdvsftpd project
On-prem
Operating Systems / unix-bsd
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
f5commercialUSNetworking Infrastructure
sendmailoss-projectCommunicationsaka sendmail switch, advanced message server
vsftpd projectoss-projectOperating Systemsaka vsftpd
fedoraprojectoss-projectUSOperating Systemsaka fedora project
and 15 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://bugzilla.redhat.com/show_bug.cgi?id=1975623
bugzilla.redhat.com
https://alpaca-attack.com/
alpaca-attack.com
https://lists.debian.org/debian-lts-announce/2022/11/msg00031.html
lists.debian.org
and 13 more references View all →

Timeline

Published
Mar 23, 2022
Last Updated
Nov 21, 2024

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