CVE-2021-22991: F5 BIG-IP Traffic Management Microkernel Buffer Overflow

Published Mar 31, 2021
·
Updated

On BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, and 12.1.x before 12.1.5.3, undisclosed requests to a virtual server may be incorrectly handled by the Traffic Management Microkernel (TMM) URI normalization, which may trigger a buffer overflow, resulting in a DoS attack. In certain situations, it may theoretically allow bypass of URL based access control or remote code execution (RCE). Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.

Other sources

The Traffic Management Microkernel of BIG-IP ASM Risk Engine has a buffer overflow vulnerability, leading to a bypassing of URL-based access controls.

— CISA

Affected Software

71 affected components
F5 BIG-IP Traffic Management Microkernel
F5 BIG-IP Access Policy Manager>=12.1.0<12.1.5.3
F5 BIG-IP Access Policy Manager>=13.1.0<13.1.3.6
F5 BIG-IP Access Policy Manager>=14.1.0<14.1.4
F5 BIG-IP Access Policy Manager>=15.1.0<15.1.2.1
F5 BIG-IP Access Policy Manager>=16.0.0<16.0.1.1
F5 BIG-IP Advanced Firewall Manager>=12.1.0<12.1.5.3
F5 BIG-IP Advanced Firewall Manager>=13.1.0<13.1.3.6
F5 BIG-IP Advanced Firewall Manager>=14.1.0<14.1.4
F5 BIG-IP Advanced Firewall Manager>=15.1.0<15.1.2.1
F5 BIG-IP Advanced Firewall Manager>=16.0.0<16.0.1.1
F5 Big-ip Advanced Web Application Firewall>=12.1.0<12.1.5.3
F5 Big-ip Advanced Web Application Firewall>=13.1.0<13.1.3.6
F5 Big-ip Advanced Web Application Firewall>=14.1.0<14.1.4
F5 Big-ip Advanced Web Application Firewall>=15.1.0<15.1.2.1
F5 Big-ip Advanced Web Application Firewall>=16.0.0<16.0.1.1
F5 BIG-IP Analytics>=12.1.0<12.1.5.3
F5 BIG-IP Analytics>=13.1.0<13.1.3.6
F5 BIG-IP Analytics>=14.1.0<14.1.4
F5 BIG-IP Analytics>=15.1.0<15.1.2.1
F5 BIG-IP Analytics>=16.0.0<16.0.1.1
F5 Big-ip Application Acceleration Manager>=12.1.0<12.1.5.3
F5 Big-ip Application Acceleration Manager>=13.1.0<13.1.3.6
F5 Big-ip Application Acceleration Manager>=14.1.0<14.1.4
F5 Big-ip Application Acceleration Manager>=15.1.0<15.1.2.1
F5 Big-ip Application Acceleration Manager>=16.0.0<16.0.1.1
F5 BIG-IP Application Security Manager>=12.1.0<12.1.5.3
F5 BIG-IP Application Security Manager>=13.1.0<13.1.3.6
F5 BIG-IP Application Security Manager>=14.1.0<14.1.4
F5 BIG-IP Application Security Manager>=15.1.0<15.1.2.1
F5 BIG-IP Application Security Manager>=16.0.0<16.0.1.1
F5 Big-ip Ddos Hybrid Defender>=12.1.0<12.1.5.3
F5 Big-ip Ddos Hybrid Defender>=13.1.0<13.1.3.6
F5 Big-ip Ddos Hybrid Defender>=14.1.0<14.1.4
F5 Big-ip Ddos Hybrid Defender>=15.1.0<15.1.2.1
F5 Big-ip Ddos Hybrid Defender>=16.0.0<16.0.1.1
F5 Big-ip Domain Name System>=12.1.0<12.1.5.3
F5 Big-ip Domain Name System>=13.1.0<13.1.3.6
F5 Big-ip Domain Name System>=14.1.0<14.1.4
F5 Big-ip Domain Name System>=15.1.0<15.1.2.1
F5 Big-ip Domain Name System>=16.0.0<16.0.1.1
F5 Big-ip Fraud Protection Service>=12.1.0<12.1.5.3
F5 Big-ip Fraud Protection Service>=13.1.0<13.1.3.6
F5 Big-ip Fraud Protection Service>=14.1.0<14.1.4
F5 Big-ip Fraud Protection Service>=15.1.0<15.1.2.1
F5 Big-ip Fraud Protection Service>=16.0.0<16.0.1.1
F5 Big-ip Global Traffic Manager>=12.1.0<12.1.5.3
F5 Big-ip Global Traffic Manager>=13.1.0<13.1.3.6
F5 Big-ip Global Traffic Manager>=14.1.0<14.1.4
F5 Big-ip Global Traffic Manager>=15.1.0<15.1.2.1
F5 Big-ip Global Traffic Manager>=16.0.0<16.0.1.1
F5 Big-ip Link Controller>=12.1.0<12.1.5.3
F5 Big-ip Link Controller>=13.1.0<13.1.3.6
F5 Big-ip Link Controller>=14.1.0<14.1.4
F5 Big-ip Link Controller>=15.1.0<15.1.2.1
F5 Big-ip Link Controller>=16.0.0<16.0.1.1
F5 Big-ip Local Traffic Manager>=12.1.0<12.1.5.3
F5 Big-ip Local Traffic Manager>=13.1.0<13.1.3.6
F5 Big-ip Local Traffic Manager>=14.1.0<14.1.4
F5 Big-ip Local Traffic Manager>=15.1.0<15.1.2.1
F5 Big-ip Local Traffic Manager>=16.0.0<16.0.1.1
F5 Big-ip Policy Enforcement Manager>=12.1.0<12.1.5.3
F5 Big-ip Policy Enforcement Manager>=13.1.0<13.1.3.6
F5 Big-ip Policy Enforcement Manager>=14.1.0<14.1.4
F5 Big-ip Policy Enforcement Manager>=15.1.0<15.1.2.1
F5 Big-ip Policy Enforcement Manager>=16.0.0<16.0.1.1
F5 SSL Orchestrator>=12.1.0<12.1.5.3
F5 SSL Orchestrator>=13.1.0<13.1.3.6
F5 SSL Orchestrator>=14.1.0<14.1.4
F5 SSL Orchestrator>=15.1.0<15.1.2.1
F5 SSL Orchestrator>=16.0.0<16.0.1.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade F5 BIG-IP to a version that resolves this vulnerability.

    Fixed in 16.0.1.1
  2. Upgrade

    Upgrade F5 BIG-IP to a version that resolves this vulnerability.

    Fixed in 15.1.2.1
  3. Upgrade

    Upgrade F5 BIG-IP to a version that resolves this vulnerability.

    Fixed in 14.1.4
  4. Upgrade

    Upgrade F5 BIG-IP to a version that resolves this vulnerability.

    Fixed in 13.1.3.6
  5. Upgrade

    Upgrade F5 BIG-IP to a version that resolves this vulnerability.

    Fixed in 12.1.5.3
  6. Upgrade

    Upgrade F5 BIG-IP ASM Risk Engine to a version that resolves this vulnerability.

    Fixed in 16.0.1.1
  7. Upgrade

    Upgrade F5 BIG-IP ASM Risk Engine to a version that resolves this vulnerability.

    Fixed in 15.1.2.1
  8. Upgrade

    Upgrade F5 BIG-IP ASM Risk Engine to a version that resolves this vulnerability.

    Fixed in 14.1.4
  9. Upgrade

    Upgrade F5 BIG-IP ASM Risk Engine to a version that resolves this vulnerability.

    Fixed in 13.1.3.6
  10. Upgrade

    Upgrade F5 BIG-IP ASM Risk Engine to a version that resolves this vulnerability.

    Fixed in 12.1.5.3
  11. Upgrade

    Upgrade F5 BIG-IP Traffic Management Microkernel to a version that resolves this vulnerability.

    Fixed in 16.0.1.1
  12. Upgrade

    Upgrade F5 BIG-IP Traffic Management Microkernel to a version that resolves this vulnerability.

    Fixed in 15.1.2.1
  13. Upgrade

    Upgrade F5 BIG-IP Traffic Management Microkernel to a version that resolves this vulnerability.

    Fixed in 14.1.4
  14. Upgrade

    Upgrade F5 BIG-IP Traffic Management Microkernel to a version that resolves this vulnerability.

    Fixed in 13.1.3.6
  15. Upgrade

    Upgrade F5 BIG-IP Traffic Management Microkernel to a version that resolves this vulnerability.

    Fixed in 12.1.5.3

Event History

Mar 31, 2021
CVE Published
via MITRE·05:23 PM
Data Sourced
via MITRE·05:23 PM
DescriptionWeakness
Jan 18, 2022
Known Exploited
via CISA·12:00 AM

Frequently Asked Questions

1

What is the severity of CVE-2021-22991?

The severity of CVE-2021-22991 is classified as critical due to the potential for unauthorized access and manipulation of data.

2

How do I fix CVE-2021-22991?

To fix CVE-2021-22991, upgrade your F5 BIG-IP software to the latest patched version that addresses this vulnerability.

3

What versions are affected by CVE-2021-22991?

CVE-2021-22991 affects F5 BIG-IP versions prior to 16.0.1.1, 15.1.2.1, 14.1.4, 13.1.3.6, and 12.1.5.3.

4

What types of software are vulnerable under CVE-2021-22991?

CVE-2021-22991 affects multiple F5 applications including BIG-IP Access Policy Manager, Advanced Firewall Manager, and Application Security Manager.

5

Is there a workaround for CVE-2021-22991?

Currently, the best practice is to apply the security update provided by F5 rather than relying on workarounds.

Company

Resources

Contact

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