Vulnerability in F5 Nginx
CVE-2021-3618
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 vi…
Vulnerability class: Improper Certificate Validation
EPSS: 0.020 (79.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.
Affected products
- F5 Nginx
- Sendmail
- Vsftpd_project Vsftpd
- Debian Debian_linux — versions 10.0
- Fedoraproject Fedora — versions 33, 34, 35
- N/a Alpaca — versions vsftpd 3.0.4, nginx 1.21.0, sendmail 8.17
Weakness classification (CWE)
Public proof-of-concept exploits
References
- secalert@redhat.com (Patch, Third Party Advisory, Issue Tracking)
- secalert@redhat.com (Third Party Advisory)
- secalert@redhat.com (mailing-list, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-3618?
- CVE-2021-3618 is a high-severity vulnerability in F5 Nginx, classified under Improper Certificate Validation. CVSS score: 7.4/10. Published 2022-03-23.
- How severe is CVE-2021-3618?
- High severity. CVSS v3 base score is 7.4 out of 10.
- Is CVE-2021-3618 known to be exploited?
- 9 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.