CVE-2020-3230: Cisco IOS and IOS XE Software Internet Key Exchange Version 2 Denial of Service Vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.7% 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 the Internet Key Exchange Version 2 (IKEv2) implementation in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to prevent IKEv2 from establishing new security associations. The vulnerability is due to incorrect handling of crafted IKEv2 SA-Init packets. An attacker could exploit this vulnerability by sending crafted IKEv2 SA-Init packets to the affected device. An exploit could allow the attacker to cause the affected device to reach the maximum incoming negotiation limits and prevent further IKEv2 security associations from being formed.

Affected products

Cisco IOS: 12.2(6)i1, 15.0(2)ej, 15.0(2)ej1, 15.0(2)ek, 15.0(2)ek1, 15.0(2)ex (+522)
Cisco IOS XE: 3.3.0sg, 3.3.0xo, 3.3.1sg, 3.3.1xo, 3.3.2sg, 3.3.2xo (+258)

References

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