Wiz
Vulnerability DatabaseCVE-2020-27721

CVE-2020-27721: 
F5 BIG-IP Virtual Edition vulnerability analysis and mitigation

Overview

CVE-2020-27721 affects BIG-IP DNS/BIG-IP LTM GSLB deployment systems in versions 16.0.0-16.0.0.1, 15.1.0-15.1.1, 14.1.0-14.1.3, 13.1.0-13.1.3.5, 12.1.0-12.1.5.2, and 11.6.1-11.6.5.2. The vulnerability was discovered and disclosed in December 2020 (NVD).

Technical details

Under certain circumstances, the BIG-IP DNS system may stop using a BIG-IP LTM virtual server for DNS response. The vulnerability has been assigned a CVSS v3.1 Base Score of 7.5 (HIGH) with a vector of CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (NVD).

Impact

The vulnerability primarily affects system availability, as it can cause the BIG-IP DNS system to stop using a BIG-IP LTM virtual server for DNS responses, potentially disrupting DNS services (NVD).

Exploitability

The vulnerability can be exploited remotely with low attack complexity and requires no privileges or user interaction (NVD).

Mitigation and workarounds

F5 has released patched versions to address this vulnerability. Users should upgrade to the appropriate fixed version for their installation (F5 Advisory).

Additional resources

Source: This report was generated using AI

Related F5 BIG-IP Virtual Edition vulnerabilities:

CVE ID

Severity

Score

Technologies

Component name

CISA KEV exploit

Has fix

Published date

CVE-2026-42920HIGH8.7
  • F5 BIG-IP Virtual Edition logoF5 BIG-IP Virtual Edition
  • cpe:2.3:a:f5:big-ip_application_security_manager
NoYesMay 13, 2026
CVE-2026-42930HIGH8.5
  • F5 BIG-IP Virtual Edition logoF5 BIG-IP Virtual Edition
  • cpe:2.3:a:f5:big-ip_access_policy_manager
NoYesMay 13, 2026
CVE-2026-42924HIGH8.5
  • F5 BIG-IP Virtual Edition logoF5 BIG-IP Virtual Edition
  • cpe:2.3:a:f5:big-ip_local_traffic_manager
NoYesMay 13, 2026
CVE-2026-42937HIGH7.1
  • F5 BIG-IP Virtual Edition logoF5 BIG-IP Virtual Edition
  • cpe:2.3:a:f5:big-ip_domain_name_system
NoYesMay 13, 2026
CVE-2026-42919HIGH7.1
  • F5 BIG-IP Virtual Edition logoF5 BIG-IP Virtual Edition
  • cpe:2.3:a:f5:big-ip_access_policy_manager
NoYesMay 13, 2026

Free Vulnerability Assessment

Benchmark your Cloud Security Posture

Evaluate your cloud security practices across 9 security domains to benchmark your risk level and identify gaps in your defenses.

Request assessment

Additional Wiz resources

Cloud Vulnerability DB

Cloud Vulnerability DB

A community-led vulnerabilities database

Cloud Threat Landscape

Cloud Threat Landscape

A threat intelligence database

PEACH

PEACH

A tenant isolation framework

Get a personalized demo

Ready to see Wiz in action?

"Best User Experience I have ever seen, provides full visibility to cloud workloads."
David EstlickCISO
"Wiz provides a single pane of glass to see what is going on in our cloud environments."
Adam FletcherChief Security Officer
"We know that if Wiz identifies something as critical, it actually is."
Greg PoniatowskiHead of Threat and Vulnerability Management
Get a demo