CVE-2026-86107: Arista Networks VeloCloud

Medium severity, CVSS 5.9. EPSS: 0.4% chance of exploitation in the next 30 days.

The VeloCloud Edge and Gateway exhibit an out-of-bounds write vulnerability when processing tunneled IP fragments between authenticated overlay neighbors. This vulnerability impacts the VeloCloud VCMP tunnel protocol only. A successful exploit can cause the affected process to terminate and restart, leading to a temporary disruption of traffic. Hosts on the internet that are unauthenticated and unable to form an overlay peer relationship can not trigger the vulnerable logic.

Affected products

• Arista Networks VeloCloud: from 1.0.0.0, before 5.2.0.0 (fixed in 5.2.0.0); from 5.2.0.0, before 5.2.7.0 (fixed in 5.2.7.0); from 6.1.0.0, before 6.1.5.0 (fixed in 6.1.5.0); from 6.4.0.0, before 6.4.2.0 (fixed in 6.4.2.0)
• Arista Networks VeloCloud Gateway: from 1.0.0.0, before 5.2.0.0 (fixed in 5.2.0.0); from 5.2.0.0, before 5.2.7.0 (fixed in 5.2.7.0); from 6.1.0.0, before 6.1.5.0 (fixed in 6.1.5.0); from 6.4.0.0, before 6.4.2.0 (fixed in 6.4.2.0)

Published 2026-09-16. Last modified 2026-09-16.