Exploited
critical
9.8
CWE
119
Advisory Published
Updated

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

First published: Wed 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.

Credit: f5sirt@f5.com f5sirt@f5.com f5sirt@f5.com

Affected SoftwareAffected VersionHow to fix
F5 BIG-IP Traffic Management Microkernel
F5 Access Policy Manager>=12.1.0<12.1.5.3
F5 Access Policy Manager>=13.1.0<13.1.3.6
F5 Access Policy Manager>=14.1.0<14.1.4
F5 Access Policy Manager>=15.1.0<15.1.2.1
F5 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 WAF/ASM>=12.1.0<12.1.5.3
F5 BIG-IP Advanced WAF/ASM>=13.1.0<13.1.3.6
F5 BIG-IP Advanced WAF/ASM>=14.1.0<14.1.4
F5 BIG-IP Advanced WAF/ASM>=15.1.0<15.1.2.1
F5 BIG-IP Advanced WAF/ASM>=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 Application Security Manager>=12.1.0<12.1.5.3
F5 Application Security Manager>=13.1.0<13.1.3.6
F5 Application Security Manager>=14.1.0<14.1.4
F5 Application Security Manager>=15.1.0<15.1.2.1
F5 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 services>=12.1.0<12.1.5.3
F5 BIG-IP fraud protection services>=13.1.0<13.1.3.6
F5 BIG-IP fraud protection services>=14.1.0<14.1.4
F5 BIG-IP fraud protection services>=15.1.0<15.1.2.1
F5 BIG-IP fraud protection services>=16.0.0<16.0.1.1
Riverbed SteelApp Traffic Manager>=12.1.0<12.1.5.3
Riverbed SteelApp Traffic Manager>=13.1.0<13.1.3.6
Riverbed SteelApp Traffic Manager>=14.1.0<14.1.4
Riverbed SteelApp Traffic Manager>=15.1.0<15.1.2.1
Riverbed SteelApp Traffic Manager>=16.0.0<16.0.1.1
F5 BIG-IP>=12.1.0<12.1.5.3
F5 BIG-IP>=13.1.0<13.1.3.6
F5 BIG-IP>=14.1.0<14.1.4
F5 BIG-IP>=15.1.0<15.1.2.1
F5 BIG-IP>=16.0.0<16.0.1.1
Riverbed SteelApp Traffic Manager>=12.1.0<12.1.5.3
Riverbed SteelApp Traffic Manager>=13.1.0<13.1.3.6
Riverbed SteelApp Traffic Manager>=14.1.0<14.1.4
Riverbed SteelApp Traffic Manager>=15.1.0<15.1.2.1
Riverbed SteelApp 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 BIG-IP SSL Orchestrator>=12.1.0<12.1.5.3
F5 BIG-IP SSL Orchestrator>=13.1.0<13.1.3.6
F5 BIG-IP SSL Orchestrator>=14.1.0<14.1.4
F5 BIG-IP SSL Orchestrator>=15.1.0<15.1.2.1
F5 BIG-IP SSL Orchestrator>=16.0.0<16.0.1.1

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Reference Links

Frequently Asked Questions

  • 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.

  • 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.

  • 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.

  • 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.

  • 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.

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