CVE-2021-23009
Status: ModifiedHigh (7.5)—
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
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Base score: 7.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.99%
- Percentile among all scored CVEs: 61
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (14)
F5 — Big-ip Access Policy ManagerF5 — Big-ip Advanced Firewall ManagerF5 — Big-ip Advanced WEB Application FirewallF5 — Big-ip AnalyticsF5 — Big-ip Application Acceleration ManagerF5 — Big-ip Application Security ManagerF5 — Big-ip Ddos Hybrid DefenderF5 — Big-ip Domain Name SystemF5 — Big-ip Fraud Protection ServiceF5 — Big-ip Global Traffic ManagerF5 — Big-ip Link ControllerF5 — Big-ip Local Traffic ManagerF5 — Big-ip Policy Enforcement ManagerF5 — Big-ip SSL Orchestrator
CWEs
- CWE-835
References
Raw JSON (NVD)
Show
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