high
7.5
CWE
400
Advisory Published
Updated

CVE-2021-23042

First published: Tue Sep 14 2021(Updated: )

On BIG-IP version 16.0.x before 16.0.1.2, 15.1.x before 15.1.3, 14.1.x before 14.1.4, 13.1.x before 13.1.4, and 12.1.x before 12.1.6, when an HTTP profile is configured on a virtual server, undisclosed requests can cause a significant increase in system resource utilization. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Credit: f5sirt@f5.com

Affected SoftwareAffected VersionHow to fix
F5 Access Policy Manager>=12.1.0<12.1.6
F5 Access Policy Manager>=13.1.0<13.1.4
F5 Access Policy Manager>=14.1.0<14.1.4
F5 Access Policy Manager>=15.1.0<15.1.3
F5 Access Policy Manager>=16.0.0<16.0.1.2
F5 BIG-IP Advanced Firewall Manager>=12.1.0<12.1.6
F5 BIG-IP Advanced Firewall Manager>=13.1.0<13.1.4
F5 BIG-IP Advanced Firewall Manager>=14.1.0<14.1.4
F5 BIG-IP Advanced Firewall Manager>=15.1.0<15.1.3
F5 BIG-IP Advanced Firewall Manager>=16.0.0<16.0.1.2
F5 BIG-IP Advanced WAF/ASM>=12.1.0<12.1.6
F5 BIG-IP Advanced WAF/ASM>=13.1.0<13.1.4
F5 BIG-IP Advanced WAF/ASM>=14.1.0<14.1.4
F5 BIG-IP Advanced WAF/ASM>=15.1.0<15.1.3
F5 BIG-IP Advanced WAF/ASM>=16.0.0<16.0.1.2
F5 BIG-IP Analytics>=12.1.0<12.1.6
F5 BIG-IP Analytics>=13.1.0<13.1.4
F5 BIG-IP Analytics>=14.1.0<14.1.4
F5 BIG-IP Analytics>=15.1.0<15.1.3
F5 BIG-IP Analytics>=16.0.0<16.0.1.2
F5 BIG-IP Application Acceleration Manager>=12.1.0<12.1.6
F5 BIG-IP Application Acceleration Manager>=13.1.0<13.1.4
F5 BIG-IP Application Acceleration Manager>=14.1.0<14.1.4
F5 BIG-IP Application Acceleration Manager>=15.1.0<15.1.3
F5 BIG-IP Application Acceleration Manager>=16.0.0<16.0.1.2
F5 Application Security Manager>=12.1.0<12.1.6
F5 Application Security Manager>=13.1.0<13.1.4
F5 Application Security Manager>=14.1.0<14.1.4
F5 Application Security Manager>=15.1.0<15.1.3
F5 Application Security Manager>=16.0.0<16.0.1.2
F5 BIG-IP DDoS Hybrid Defender>=12.1.0<12.1.6
F5 BIG-IP DDoS Hybrid Defender>=13.1.0<13.1.4
F5 BIG-IP DDoS Hybrid Defender>=14.1.0<14.1.4
F5 BIG-IP DDoS Hybrid Defender>=15.1.0<15.1.3
F5 BIG-IP DDoS Hybrid Defender>=16.0.0<16.0.1.2
F5 BIG-IP>=12.1.0<12.1.6
F5 BIG-IP>=13.1.0<13.1.4
F5 BIG-IP>=14.1.0<14.1.4
F5 BIG-IP>=15.1.0<15.1.3
F5 BIG-IP>=16.0.0<16.0.1.2
F5 BIG-IP Fraud Protection Service>=12.1.0<12.1.6
F5 BIG-IP Fraud Protection Service>=13.1.0<13.1.4
F5 BIG-IP Fraud Protection Service>=14.1.0<14.1.4
F5 BIG-IP Fraud Protection Service>=15.1.0<15.1.3
F5 BIG-IP Fraud Protection Service>=16.0.0<16.0.1.2
Riverbed SteelApp Traffic Manager>=12.1.0<12.1.6
Riverbed SteelApp Traffic Manager>=13.1.0<13.1.4
Riverbed SteelApp Traffic Manager>=14.1.0<14.1.4
Riverbed SteelApp Traffic Manager>=15.1.0<15.1.3
Riverbed SteelApp Traffic Manager>=16.0.0<16.0.1.2
F5 BIG-IP Link Controller>=12.1.0<12.1.6
F5 BIG-IP Link Controller>=13.1.0<13.1.4
F5 BIG-IP Link Controller>=14.1.0<14.1.4
F5 BIG-IP Link Controller>=15.1.0<15.1.3
F5 BIG-IP Link Controller>=16.0.0<16.0.1.2
Riverbed SteelApp Traffic Manager>=12.1.0<12.1.6
Riverbed SteelApp Traffic Manager>=13.1.0<13.1.4
Riverbed SteelApp Traffic Manager>=14.1.0<14.1.4
Riverbed SteelApp Traffic Manager>=15.1.0<15.1.3
Riverbed SteelApp Traffic Manager>=16.0.0<16.0.1.2
F5 BIG-IP Policy Enforcement Manager>=12.1.0<12.1.6
F5 BIG-IP Policy Enforcement Manager>=13.1.0<13.1.4
F5 BIG-IP Policy Enforcement Manager>=14.1.0<14.1.4
F5 BIG-IP Policy Enforcement Manager>=15.1.0<15.1.3
F5 BIG-IP Policy Enforcement Manager>=16.0.0<16.0.1.2
F5 BIG-IP SSL Orchestrator>=12.1.0<12.1.6
F5 BIG-IP SSL Orchestrator>=13.1.0<13.1.4
F5 BIG-IP SSL Orchestrator>=14.1.0<14.1.4
F5 BIG-IP SSL Orchestrator>=15.1.0<15.1.3
F5 BIG-IP SSL Orchestrator>=16.0.0<16.0.1.2

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-23042?

    CVE-2021-23042 is classified as a high severity vulnerability due to the significant increase in system resource utilization it can cause.

  • How do I fix CVE-2021-23042?

    To mitigate CVE-2021-23042, upgrade to the latest version of the affected F5 BIG-IP products where this vulnerability has been addressed.

  • Which versions of F5 BIG-IP are affected by CVE-2021-23042?

    CVE-2021-23042 affects F5 BIG-IP versions before 16.0.1.2, 15.1.3, 14.1.4, 13.1.4, and 12.1.6.

  • What type of issue does CVE-2021-23042 represent?

    CVE-2021-23042 represents a resource exhaustion issue that can result from specific HTTP profile configurations on virtual servers.

  • Is there a workaround for CVE-2021-23042?

    While the best practice is to update to a patched version, temporary measures may include disabling or reconfiguring the HTTP profiles to minimize exposure.

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