What is CVE-2026-86107?

CVE-2026-86107 is a medium-severity vulnerability in Arista Networks Velocloud, classified under Out-of-bounds Write. CVSS score: 5.9/10. Published 2026-09-16.

How severe is CVE-2026-86107?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Buffer overflow in Arista Networks Velocloud

CVE-2026-86107

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.

Vulnerability class: Buffer Overflow

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

psirt@arista.com (vendor-advisory)

Frequently asked questions

What is CVE-2026-86107?: CVE-2026-86107 is a medium-severity vulnerability in Arista Networks Velocloud, classified under Out-of-bounds Write. CVSS score: 5.9/10. Published 2026-09-16.
How severe is CVE-2026-86107?: Medium severity. CVSS v3 base score is 5.9 out of 10.