CVE-2021-3618

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Summary

CVECVE-2021-3618
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2022-03-23 20:15:00 UTC
Updated2023-02-09 02:03:00 UTC
DescriptionALPACA 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.

Risk And Classification

Problem Types: CWE-295

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Debian Debian Linux 10.0 All All All
Application F5 Nginx All All All All
Operating System Fedoraproject Fedora 33 All All All
Operating System Fedoraproject Fedora 34 All All All
Operating System Fedoraproject Fedora 35 All All All
Application Sendmail Sendmail All All All All
Application Vsftpd Project Vsftpd All All All All

References

ReferenceSourceLinkTags
#991328 - nginx: CVE-2021-3618 - Debian Bug report logs MISC bugs.debian.org
ALPACA Attack MISC alpaca-attack.com
[SECURITY] [DLA 3203-1] nginx security update MLIST lists.debian.org
Mail: max_errors directive. · nginx/nginx@173f16f · GitHub MISC github.com
CVE-2021-3618 | Ubuntu MISC ubuntu.com
#991329 - vsftpd: CVE-2021-3618 - Debian Bug report logs MISC bugs.debian.org
#991331 - sendmail: CVE-2021-3618 - Debian Bug report logs MISC bugs.debian.org
1975623 – (ALPACA, CVE-2021-3618) CVE-2021-3618 ALPACA: Application Layer Protocol Confusion - Analyzing and Mitigating Cracks in TLS Authentication MISC bugzilla.redhat.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 180863 Debian Security Update for nginx (CVE-2021-3618)
  • 181243 Debian Security Update for nginx (DLA 3203-1)
  • 198741 Ubuntu Security Notification for nginx Vulnerabilities (USN-5371-1)
  • 198766 Ubuntu Security Notification for nginx Vulnerability (USN-5371-2)
  • 199758 Ubuntu Security Notification for vsftpd Vulnerability (USN-6379-1)
  • 281682 Fedora Security Update for nginx (FEDORA-2021-031436cb0e)
  • 281683 Fedora Security Update for nginx (FEDORA-2021-a856024cca)
  • 282004 Fedora Security Update for vsftpd (FEDORA-2021-67164401ae)
  • 296100 Oracle Solaris 11.4 Support Repository Update (SRU) 58.144.3 Missing (CPUAPR2023)
  • 352825 Amazon Linux Security Advisory for nginx: AL2012-2021-349
  • 354364 Amazon Linux Security Advisory for sendmail : ALAS2022-2022-171
  • 354435 Amazon Linux Security Advisory for vsftpd : ALAS2022-2022-136
  • 354479 Amazon Linux Security Advisory for sendmail : ALAS2022-2022-132
  • 354521 Amazon Linux Security Advisory for vsftpd : ALAS2022-2022-172
  • 355125 Amazon Linux Security Advisory for vsftpd : ALAS2023-2023-019
  • 355154 Amazon Linux Security Advisory for sendmail : ALAS2023-2023-018
  • 356183 Amazon Linux Security Advisory for nginx : ALASNGINX1-2023-002
  • 356485 Amazon Linux Security Advisory for nginx : ALAS2NGINX1-2023-002
  • 357015 Amazon Linux Security Advisory for vsftpd : ALAS2-2024-2431
  • 501758 Alpine Linux Security Update for nginx
  • 504189 Alpine Linux Security Update for nginx
  • 670718 EulerOS Security Update for nginx (EulerOS-SA-2021-2476)
  • 670755 EulerOS Security Update for nginx (EulerOS-SA-2021-2513)
  • 671013 EulerOS Security Update for nginx (EulerOS-SA-2021-2599)
  • 752623 SUSE Enterprise Linux Security Update for vsftpd (SUSE-SU-2022:3383-1)
  • 752633 SUSE Enterprise Linux Security Update for vsftpd (SUSE-SU-2022:3458-1)
  • 752635 SUSE Enterprise Linux Security Update for vsftpd (SUSE-SU-2022:3457-1)
  • 752767 SUSE Enterprise Linux Security Update for vsftpd (SUSE-SU-2022:3888-1)
  • 752816 SUSE Enterprise Linux Security Update for nginx (SUSE-SU-2022:4192-1)
  • 752861 SUSE Enterprise Linux Security Update for nginx (SUSE-SU-2022:4201-1)
  • 752949 SUSE Enterprise Linux Security Update for nginx (SUSE-SU-2022:4266-1)
  • 752963 SUSE Enterprise Linux Security Update for nginx (SUSE-SU-2022:4265-1)
  • 753456 SUSE Enterprise Linux Security Update for vsftpd (SUSE-SU-2022:3320-1)
  • 900785 Common Base Linux Mariner (CBL-Mariner) Security Update for vsftpd (9183)
  • 900850 Common Base Linux Mariner (CBL-Mariner) Security Update for nginx (9181)
  • 900980 Common Base Linux Mariner (CBL-Mariner) Security Update for nginx (9188)
  • 901095 Common Base Linux Mariner (CBL-Mariner) Security Update for vsftpd (9190-1)
  • 901274 Common Base Linux Mariner (CBL-Mariner) Security Update for sendmail (9220)
  • 901307 Common Base Linux Mariner (CBL-Mariner) Security Update for vsftpd (9183-1)
  • 901335 Common Base Linux Mariner (CBL-Mariner) Security Update for nginx (9181-1)
  • 902102 Common Base Linux Mariner (CBL-Mariner) Security Update for nginx (9188-1)
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