CVE-2020-5949

Severity: high (CVSS 7.5 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

Description

On BIG-IP versions 14.0.0-14.0.1 and 13.1.0-13.1.3.4, certain traffic pattern sent to a virtual server configured with an FTP profile can cause the FTP channel to break.

Affected products

F5 BIG-IP APM: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
BIG-IP: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 Big-Ip Advanced Web Application Firewall: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 Big-Ip Analytics: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 Networks, Inc. BIG-IP (AAM): from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
BIG-IP ASM: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 Big-Ip Ddos Hybrid Defender: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 BIG-IP DNS: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 Big-Ip Fraud Protection Service: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 Big-Ip Global Traffic Manager: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 Big-Ip Link Controller: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 BIG-IP (LTM): from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 Networks, Inc. BIG-IP (PEM): from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0
F5 Big-Ip Ssl Orchestrator: from 13.1.0 before 13.1.3.5; from 14.0.0 before 14.1.0 — fixed in 13.1.3.5, 14.1.0

How to fix

Upgrade to a fixed version: F5 BIG-IP APM 13.1.3.5, 14.1.0; BIG-IP 13.1.3.5, 14.1.0; F5 Big-Ip Advanced Web Application Firewall 13.1.3.5, 14.1.0; F5 Big-Ip Analytics 13.1.3.5, 14.1.0; F5 Networks, Inc. BIG-IP (AAM) 13.1.3.5, 14.1.0; BIG-IP ASM 13.1.3.5, 14.1.0; F5 Big-Ip Ddos Hybrid Defender 13.1.3.5, 14.1.0; F5 BIG-IP DNS 13.1.3.5, 14.1.0; F5 Big-Ip Fraud Protection Service 13.1.3.5, 14.1.0; F5 Big-Ip Global Traffic Manager 13.1.3.5, 14.1.0; F5 Big-Ip Link Controller 13.1.3.5, 14.1.0; F5 BIG-IP (LTM) 13.1.3.5, 14.1.0. Check the vendor advisory for mitigations.

References

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