CVE-2020-3228: Cisco IOS

High severity, CVSS 8.6. EPSS: 1.8% chance of exploitation in the next 30 days.

A vulnerability in Security Group Tag Exchange Protocol (SXP) in Cisco IOS Software, Cisco IOS XE Software, and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability exists because crafted SXP packets are mishandled. An attacker could exploit this vulnerability by sending specifically crafted SXP packets to the affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Affected products

• Cisco IOS: version 12.2(6)i1 only; version 15.1(1)sy only; version 15.1(1)sy1 only; version 15.1(1)sy2 only; version 15.1(1)sy3 only; version 15.1(1)sy4 only; …
• Cisco IOS XE: version 3.3.0se only; version 3.3.0xo only; version 3.3.1se only; version 3.3.1xo only; version 3.3.2se only; version 3.3.2xo only; …
• Cisco NX-OS: version 5.2(1)sv3(3.1) only; version 5.2(1)sv3(3.15) only; version 5.2(1)sv3(4.1) only; version 5.2(1)sv3(4.1a) only; version 5.2(1)sv3(4.1b) only; version 5.2(1)sv5(1.1) only; …

Published 2020-06-03. Last modified 2026-06-17.