BIG-IP
CVE-2026-39458: BIG-IP DNS Cache vulnerability
When a BIG-IP is configured with DNS caching (Such as a DNS profile with caching enabled, SSL Orchestrator, Advanced WAF DoS protection), undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| BIG-IP 21.1 | Not affected |
| BIG-IP 21.0 | 21.0.0.1 or later |
| BIG-IP 17.5 | 17.5.1.6 or later |
| BIG-IP 17.1 | 17.1.3.2 or later |
| BIG-IP 16.1 | * or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
When a BIG-IP is configured with DNS caching (Such as a DNS profile with caching enabled, SSL Orchestrator, Advanced WAF DoS protection), undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Workarounds
CHANGE_ME
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 12 Oct 2026.