CVE-2021-22976: High severity F5 Big-ip Advanced Web Application Firewall vulnerability

Published Feb 12, 2021
·
Updated

On BIG-IP Advanced WAF and ASM version 16.0.x before 16.0.1.1, 15.1.x before 15.1.2, 14.1.x before 14.1.3.1, 13.1.x before 13.1.3.6, and all 12.1.x versions, when the BIG-IP ASM system processes WebSocket requests with JSON payloads, an unusually large number of parameters can cause excessive CPU usage in the BIG-IP ASM bd process. Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.

Affected Software

10 affected components
F5 Big-ip Advanced Web Application Firewall>=12.1.0<=12.1.5
F5 Big-ip Advanced Web Application Firewall>=13.1.0<13.1.3.6
F5 Big-ip Advanced Web Application Firewall>=14.1.0<14.1.3.1
F5 Big-ip Advanced Web Application Firewall>=15.1.0<15.1.2
F5 Big-ip Advanced Web Application Firewall>=16.0.0<16.0.1.1
F5 BIG-IP Application Security Manager>=12.1.0<=12.1.5
F5 BIG-IP Application Security Manager>=13.1.0<13.1.3.6
F5 BIG-IP Application Security Manager>=14.1.0<14.1.3.1
F5 BIG-IP Application Security Manager>=15.1.0<15.1.2
F5 BIG-IP Application Security Manager>=16.0.0<16.0.1.1

Event History

Feb 12, 2021
CVE Published
via MITRE·05:43 PM
Data Sourced
via MITRE·05:43 PM
DescriptionWeakness

Frequently Asked Questions

1

What is the severity of CVE-2021-22976?

The severity of CVE-2021-22976 is classified as a medium risk vulnerability.

2

How do I fix CVE-2021-22976?

To fix CVE-2021-22976, upgrade to the latest version of BIG-IP Advanced WAF/ASM or BIG-IP Application Security Manager as specified in the security advisory.

3

What products are affected by CVE-2021-22976?

CVE-2021-22976 affects various versions of F5 BIG-IP Advanced WAF, ASM, and Application Security Manager including versions prior to 12.1.5.

4

What kind of attack does CVE-2021-22976 enable?

CVE-2021-22976 can enable a denial-of-service attack by causing excessive CPU resource usage when processing WebSocket requests with large JSON payloads.

5

When was CVE-2021-22976 published?

CVE-2021-22976 was published in March 2021.

Contact

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