The version of F5 Networks BIG-IP installed on the remote host is prior to 11.6.5.3 / 12.1.6 / 13.1.3.5 / 14.1.2.7 / 15.1.0.5 / 16.0.0. It is, therefore, affected by multiple vulnerabilities as referenced in the K37661551 advisory.

    CVE-2020-12662Unbound before 1.10.1 has Insufficient Control of Network Message Volume, aka an     NXNSAttack issue. This is triggered by random subdomains in the NSDNAME in NS     records.CVE-2020-12663Unbound before 1.10.1 has an infinite loop via malformed DNS answers received from     upstream servers.ImpactThere are three types of DNS cache configurations available on the BIG-IP system: a     transparent cache, a resolver cache, and a validating resolver cache. Only BIG-IP systems licensed for DNS     services and using the DNS Cache feature are vulnerable.Notes:The DNS Cache feature is available only when     you licensethe BIG-IP systemfor DNS Services, but you do NOT have to provisionthe BIG-IP GTM or BIG-     IP DNS moduleon your BIG-IP system.Starting with BIG-IP 12.0.0, F5 renamed BIG-IP GTM to BIG-IP DNS.DNS     Express does not use Unbound and is not vulnerable to either CVE-2020-12662 or     CVE-2020-12663.CVE-2020-12662When the DNS Cache feature is enabled on the BIG-IP system, an attacker may     exploit this vulnerability to generate a large number of communications between the BIG-IP system and the     victim's authoritative DNS server to cause a denial-of-service (DoS) attack.Note: For more information     about NXNSAttack, refer to theNXNSAttack research paper.CVE-2020-12663A remote attacker may be able to     perform a DoS attack on a DNS cache configured on the BIG-IP system by causing Unbound to become     unresponsive.

Tenable has extracted the preceding description block directly from the F5 Networks BIG-IP security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Detections

Analytics

F5 Networks BIG-IP : Unbound DNS Cache vulnerabilities (K37661551)

high Nessus Plugin ID 138233

Version 1.9

Version 1.8

Version 1.9 Apr 7, 2026, 7:26 PM Plugin metadata Plugin Feed: 202604071926
Version 1.8 Nov 3, 2023, 7:56 AM CVSSv2 score source (set to "CVE-2020-12663") Detection (updated detection logic) Plugin metadata Plugin Feed: 202311030756