CVE-2020-3351: Cisco SD-WAN Solution Software Denial of Service Vulnerability

Severity: high (CVSS 8.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-07-16 · updated 2026-06-17
Weakness: CWE-399

Description

A vulnerability in Cisco SD-WAN Solution Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper validation of fields in Cisco SD-WAN peering messages that are encapsulated in UDP packets. An attacker could exploit this vulnerability by sending crafted UDP messages to the targeted system. A successful exploit could allow the attacker to cause services on the device to fail, resulting in a DoS condition that could impact the targeted device and other devices that depend on it.

Affected products

Cisco SD-WAN vManage: before 17.2.7; from 17.2.8 before 18.3.0 — fixed in 17.2.7, 18.3.0
Cisco Vedge Cloud Router: all versions
Cisco Vsmart Controller: all versions

How to fix

Upgrade to a fixed version: Cisco SD-WAN vManage 17.2.7, 18.3.0. Check the vendor advisory for mitigations.

References

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