BIG-IP
CVE-2026-42781: BIG-IP FastL4 virtual server vulnerability
When embedded Packet Velocity Acceleration (ePVA) acceleration is configured, undisclosed local ethernet traffic can cause an increase in ePVA and Traffic Management Microkernel (TMM) resource utilization.
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 (r5000 rSeries, r10000 rSeries, r12000 rSeries, BX110 blades on VELOS, BX520 blades on VELOS) 16.1, 21.1 | Not affected |
| BIG-IP (r5000 rSeries, r10000 rSeries, r12000 rSeries, BX110 blades on VELOS, BX520 blades on VELOS) 21.0 | 21.0.0.1 or later |
| BIG-IP (r5000 rSeries, r10000 rSeries, r12000 rSeries, BX110 blades on VELOS, BX520 blades on VELOS) 17.5 | 17.5.1.4 or later |
| BIG-IP (r5000 rSeries, r10000 rSeries, r12000 rSeries, BX110 blades on VELOS, BX520 blades on VELOS) 17.1 | 17.1.3.1 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
When embedded Packet Velocity Acceleration (ePVA) acceleration is configured, undisclosed local ethernet traffic can cause an increase in ePVA and Traffic Management Microkernel (TMM) resource utilization. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 12 Oct 2026.