CVE-2026-86107 PUBLISHED

Security Advisory 0180

Assigner: Arista
Reserved: 05.09.2026 Published: 16.09.2026 Updated: 16.09.2026

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.

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 5.9

Attack Vector	Network	Scope	Unchanged
Attack Complexity	High	Confidentiality Impact	None
Privileges Required	None	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

CVSS Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.2

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	High	Integrity	None	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	Arista Networks
Product	VeloCloud
Versions	Default: unaffected affected from 1.0.0.0 to 5.2.0.0 (excl.) affected from 5.2.0.0 to 5.2.7.0 (excl.) affected from 6.1.0.0 to 6.1.5.0 (excl.) affected from 6.4.0.0 to 6.4.2.0 (excl.)

Vendor	Arista Networks
Product	VeloCloud Gateway
Versions	Default: unaffected affected from 1.0.0.0 to 5.2.0.0 (excl.) affected from 5.2.0.0 to 5.2.7.0 (excl.) affected from 6.1.0.0 to 6.1.5.0 (excl.) affected from 6.4.0.0 to 6.4.2.0 (excl.)

Affected Configurations

The vulnerability requires an authenticated VCMP tunnel to be established between a target VeloCloud Edge or Gateway and a malicious peer.

Workarounds

No mitigation is available for this issue. Customers should restrict overlay peer relationships to trusted devices and monitor for unexpected fragmentation behavior.

Solutions

The following releases contain the fix: - 5.2.7.0 and later in the 5.2.x train - 6.1.5.0 and later in the 6.1.x train - 6.4.2.0 and later in the 6.4.x train - 7.0.0 and later

No hotfix is available for this issue.

References

https://www.arista.com/en/support/advisories-notices/security-advisory/24736-security-advisory-0180

Problem Types

CWE-787 Out-of-bounds Write CWE

Impacts

CAPEC-100 Overflow Buffers