Skip to content
Fencer Intel
high 7.5

CVE-2021-23011 json

On versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.3, 14.1.x before 14.1.4, 13.1.x before 13.1.4, 12.1.x before 12.1.6, and 11.6.x befo…

published 5y ago modified 4mo ago also EUVD-2021-10129

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 versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.3, 14.1.x before 14.1.4, 13.1.x before 13.1.4, 12.1.x before 12.1.6, and 11.6.x before 11.6.5.3, when the BIG-IP system is buffering packet fragments for reassembly, the Traffic Management Microkernel (TMM) may consume an excessive amount of resources, eventually leading to a restart and failover event. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Patch / fix

  • f5 big-ip_access_policy_manager 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_advanced_firewall_manager 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_advanced_web_application_firewall 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_analytics 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_application_acceleration_manager 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_application_security_manager 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_ddos_hybrid_defender 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_domain_name_system 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_fraud_protection_service 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_global_traffic_manager 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_link_controller 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_local_traffic_manager 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_policy_enforcement_manager 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1
  • f5 big-ip_ssl_orchestrator 11.6.5.3, 12.1.6, 13.1.4, 14.1.4, 15.1.3, 16.0.1.1

Is CVE-2021-23011 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Exploit prediction

0.96% chance of exploitation in the next 30 days, higher than 61% of all scored CVEs (FIRST EPSS, 2026-11-09).

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 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

  • n/a BIG-IP

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.