CVE-2020-3228: Cisco IOS, IOS XE, and NX-OS Software Security Group Tag Exchange Protocol Denial of Service Vulnerability

Severity: high (CVSS 8.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-06-03 · updated 2026-06-17
Weakness: CWE-20

Description

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: 12.2(6)i1, 15.1(1)sy, 15.1(1)sy1, 15.1(1)sy2, 15.1(1)sy3, 15.1(1)sy4 (+251)
Cisco IOS XE: 3.3.0se, 3.3.0xo, 3.3.1se, 3.3.1xo, 3.3.2se, 3.3.2xo (+213)
Cisco NX-OS: 5.2(1)sv3(3.1), 5.2(1)sv3(3.15), 5.2(1)sv3(4.1), 5.2(1)sv3(4.1a), 5.2(1)sv3(4.1b), 5.2(1)sv5(1.1) (+3)

References

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