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Fencer Intel
high 7.5

CVE-2021-22999 json

On versions 15.0.x before 15.1.0 and 14.1.x before 14.1.4, the BIG-IP system provides an option to connect HTTP/2 clients to HTTP/1.x serve…

published 5y ago modified 4mo ago also EUVD-2021-10117

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 62%
public exploits
0
none known

Summary

On versions 15.0.x before 15.1.0 and 14.1.x before 14.1.4, the BIG-IP system provides an option to connect HTTP/2 clients to HTTP/1.x servers. When a client is slow to accept responses and it closes a connection prematurely, the BIG-IP system may indefinitely retain some streams unclosed. Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.

Patch / fix

  • f5 big-ip_access_policy_manager 14.1.4, 15.1.0
  • f5 big-ip_advanced_firewall_manager 14.1.4, 15.1.0
  • f5 big-ip_advanced_web_application_firewall 14.1.4, 15.1.0
  • f5 big-ip_analytics 14.1.4, 15.1.0
  • f5 big-ip_application_acceleration_manager 14.1.4, 15.1.0
  • f5 big-ip_application_security_manager 14.1.4, 15.1.0
  • f5 big-ip_ddos_hybrid_defender 14.1.4, 15.1.0
  • f5 big-ip_domain_name_system 14.1.4, 15.1.0
  • f5 big-ip_fraud_protection_service 14.1.4, 15.1.0
  • f5 big-ip_global_traffic_manager 14.1.4, 15.1.0
  • f5 big-ip_link_controller 14.1.4, 15.1.0
  • f5 big-ip_local_traffic_manager 14.1.4, 15.1.0
  • f5 big-ip_policy_enforcement_manager 14.1.4, 15.1.0
  • f5 ssl_orchestrator 14.1.4, 15.1.0

Is CVE-2021-22999 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.

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Exploit prediction

1.00% chance of exploitation in the next 30 days, higher than 62% 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

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.