CVE-2020-5938

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-10-29 · updated 2026-06-17
Weakness: CWE-326

Description

On BIG-IP 13.1.0-13.1.3.4, 12.1.0-12.1.5.2, and 11.6.1-11.6.5.2, when negotiating IPSec tunnels with configured, authenticated peers, the peer may negotiate a different key length than the BIG-IP configuration would otherwise allow.

Affected products

F5 BIG-IP APM: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
BIG-IP: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 Big-Ip Advanced Web Application Firewall: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 Big-Ip Analytics: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 Networks, Inc. BIG-IP (AAM): from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
BIG-IP ASM: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 Big-Ip Ddos Hybrid Defender: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 BIG-IP DNS: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 Big-Ip Fraud Protection Service: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 Big-Ip Global Traffic Manager: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 Big-Ip Link Controller: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 BIG-IP (LTM): from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 Networks, Inc. BIG-IP (PEM): from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4
F5 SSL Orchestrator: from 11.6.1 through 11.6.5.2; from 12.1.0 through 12.1.5.2; from 13.1.0 through 13.1.3.4

References

Get alerted when CVE-2020-5938 or the next vulnerability affects your stack