CVE-2020-5948

Severity: critical (CVSS 9.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-12-11 · updated 2026-06-17
Weakness: CWE-79

Description

On BIG-IP versions 16.0.0-16.0.0.1, 15.1.0-15.1.0.5, 14.1.0-14.1.2.7, 13.1.0-13.1.3.4, 12.1.0-12.1.5.2, and 11.6.1-11.6.5.2, undisclosed endpoints in iControl REST allow for a reflected XSS attack, which could lead to a complete compromise of the BIG-IP system if the victim user is granted the admin role.

Affected products

F5 BIG-IP APM: from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
BIG-IP: from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
F5 Big-Ip Analytics: from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
F5 Networks, Inc. BIG-IP (AAM): from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
BIG-IP ASM: from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
F5 BIG-IP DNS: from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
F5 Big-Ip Fraud Protection Service: from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
F5 Big-Ip Global Traffic Manager: from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
F5 Big-Ip Link Controller: from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
F5 BIG-IP (LTM): from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1
F5 Networks, Inc. BIG-IP (PEM): from 13.1.0 before 13.1.3.5; from 14.1.0 before 14.1.2.8; from 15.0.0 before 15.1.1; 16.0.0 — fixed in 13.1.3.5, 14.1.2.8, 15.1.1

How to fix

Upgrade to a fixed version: F5 BIG-IP APM 13.1.3.5, 14.1.2.8, 15.1.1; BIG-IP 13.1.3.5, 14.1.2.8, 15.1.1; F5 Big-Ip Analytics 13.1.3.5, 14.1.2.8, 15.1.1; F5 Networks, Inc. BIG-IP (AAM) 13.1.3.5, 14.1.2.8, 15.1.1; BIG-IP ASM 13.1.3.5, 14.1.2.8, 15.1.1; F5 BIG-IP DNS 13.1.3.5, 14.1.2.8, 15.1.1; F5 Big-Ip Fraud Protection Service 13.1.3.5, 14.1.2.8, 15.1.1; F5 Big-Ip Global Traffic Manager 13.1.3.5, 14.1.2.8, 15.1.1; F5 Big-Ip Link Controller 13.1.3.5, 14.1.2.8, 15.1.1; F5 BIG-IP (LTM) 13.1.3.5, 14.1.2.8, 15.1.1; F5 Networks, Inc. BIG-IP (PEM) 13.1.3.5, 14.1.2.8, 15.1.1. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2020-5948 or the next vulnerability affects your stack