CVE-2021-23009
mediumpriority · track · 30EPSS 0.010 · 62 %ileEUUSEPSS · scored 2026-10-27
On BIG-IP version 16.0.x before 16.0.1.1 and 15.1.x before 15.1.3, malformed HTTP/2 requests may cause an infinite loop which causes a Denial of Service for Data Plane traffic. TMM takes the configured HA action when the TMM process is aborted. There is no control plane exposure, this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (29)
Products and version ranges known to be affected.
- f5 big-ip access policy manager15.1.0 → 15.1.3nvdUScpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
- f5 big-ip access policy manager16.0.0 → 16.0.1.1nvdUScpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
- f5 big-ip advanced firewall manager15.1.0 → 15.1.3nvdUScpe:2.3:a:f5:big-ip_advanced_firewall_manager:*:*:*:*:*:*:*:*
- f5 big-ip advanced firewall manager16.0.0 → 16.0.1.1nvdUScpe:2.3:a:f5:big-ip_advanced_firewall_manager:*:*:*:*:*:*:*:*
- f5 big-ip advanced web application firewall15.1.0 → 15.1.3nvdUScpe:2.3:a:f5:big-ip_advanced_web_application_firewall:*:*:*:*:*:*:*:*
- f5 big-ip advanced web application firewall16.0.0 → 16.0.1.1nvdUScpe:2.3:a:f5:big-ip_advanced_web_application_firewall:*:*:*:*:*:*:*:*
- f5 big-ip application acceleration manager15.1.0 → 15.1.3nvdUScpe:2.3:a:f5:big-ip_application_acceleration_manager:*:*:*:*:*:*:*:*
- f5 big-ip application acceleration manager16.0.0 → 16.0.1.1nvdUScpe:2.3:a:f5:big-ip_application_acceleration_manager:*:*:*:*:*:*:*:*
- f5 big-ip application security manager15.1.0 → 15.1.3nvdUScpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*
- f5 big-ip application security manager16.0.0 → 16.0.1.1nvdUScpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*
- f5 big-ip ddos hybrid defender15.1.0 → 15.1.3nvdUScpe:2.3:a:f5:big-ip_ddos_hybrid_defender:*:*:*:*:*:*:*:*
- f5 big-ip ddos hybrid defender16.0.0 → 16.0.1.1nvdUScpe:2.3:a:f5:big-ip_ddos_hybrid_defender:*:*:*:*:*:*:*:*
- f5 big-ip domain name system15.1.0 → 15.1.3nvdUScpe:2.3:a:f5:big-ip_domain_name_system:*:*:*:*:*:*:*:*
- f5 big-ip domain name system16.0.0 → 16.0.1.1nvdUScpe:2.3:a:f5:big-ip_domain_name_system:*:*:*:*:*:*:*:*
- f5 big-ip fraud protection service15.1.0 → 15.1.3nvdUScpe:2.3:a:f5:big-ip_fraud_protection_service:*:*:*:*:*:*:*:*
- f5 big-ip fraud protection service16.0.0 → 16.0.1.1nvdUScpe:2.3:a:f5:big-ip_fraud_protection_service:*:*:*:*:*:*:*:*
- f5 big-ip global traffic manager15.1.0 → 15.1.3nvdUScpe:2.3:a:f5:big-ip_global_traffic_manager:*:*:*:*:*:*:*:*
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://support.f5.com/csp/article/K90603426cnnvd
- https://vigilance.fr/vulnerability/F5-BIG-IP-overload-via-HTTP-2-35192cnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.1459cnnvd
- https://www.cybersecurity-help.cz/vdb/SB2021042917cnnvd
- https://support.f5.com/csp/article/K90603426enisa_euvd
- https://support.f5.com/csp/article/K90603426Vendor Advisorynvd
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