Resource exhaustion in F5 Networks products - CVE-2021-22998

Vulnerability identifier: #VU51419

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2021-22998

CWE-ID: CWE-400

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to SYN flood protection thresholds are not enforced in secure network address translation (SNAT) listeners. A remote attacker can perform SYN flood class attacks.

BIG-IP AAM
BIG-IP DNS
BIG-IP Link Controller
BIG-IP FPS
BIG-IP Analytics
BIG-IP GTM
BIG-IP LTM
BIG-IP APM
BIG-IP AFM
BIG-IP ASM
BIG-IP PEM
BIG-IP

Install updates from vendor's website.

BIG-IP AAM - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP FPS - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP Analytics - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP DNS - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP Link Controller - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP GTM - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP LTM - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP APM - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP AFM - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP ASM - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
BIG-IP PEM - addressed in versions 11.6.5.3, 12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1

• https://support.f5.com/csp/article/K31934524

• SYN flood denial of service in BIG-IP SNAT implementation