CVE-2021-23000 json
On BIG-IP versions 13.1.3.4-13.1.3.6 and 12.1.5.2, if the tmm.http.rfc.enforcement BigDB key is enabled in a BIG-IP system, or the Bad host…
published 2021-03-31 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-10118
- cvss
- 7.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 61%
- public exploits
- 0
- none known
Summary
On BIG-IP versions 13.1.3.4-13.1.3.6 and 12.1.5.2, if the tmm.http.rfc.enforcement BigDB key is enabled in a BIG-IP system, or the Bad host header value is checked in the AFM HTTP security profile associated with a virtual server, in rare instances, a specific sequence of malicious requests may cause TMM to restart. Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.
Patch / fix
- f5 big-ip_access_policy_manager 13.1.3.6
- f5 big-ip_advanced_firewall_manager 13.1.3.6
- f5 big-ip_advanced_web_application_firewall 13.1.3.6
- f5 big-ip_analytics 13.1.3.6
- f5 big-ip_application_acceleration_manager 13.1.3.6
- f5 big-ip_application_security_manager 13.1.3.6
- f5 big-ip_ddos_hybrid_defender 13.1.3.6
- f5 big-ip_domain_name_system 13.1.3.6
- f5 big-ip_fraud_protection_service 13.1.3.6
- f5 big-ip_global_traffic_manager 13.1.3.6
- f5 big-ip_link_controller 13.1.3.6
- f5 big-ip_local_traffic_manager 13.1.3.6
- f5 big-ip_policy_enforcement_manager 13.1.3.6
- f5 ssl_orchestrator 13.1.3.6
Exploit prediction
0.97% chance of exploitation in the next 30 days, higher than 61% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:N/A:P |
Affected products
- n/a BIG-IP
References
-
support.f5.com
/csp/article/K34441555
vendor-advisory
Sources
- CVE List CVE-2021-23000
- NVD CVE-2021-23000
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