CVE-2022-20920: Cisco IOS and IOS XE Software SSH Denial of Service Vulnerability

Severity: high (CVSS 7.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-10-10 · updated 2026-06-17
Weakness: CWE-755

Description

A vulnerability in the SSH implementation of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to cause an affected device to reload. This vulnerability is due to improper handling of resources during an exceptional situation. An attacker could exploit this vulnerability by continuously connecting to an affected device and sending specific SSH requests. A successful exploit could allow the attacker to cause the affected device to reload.

Affected products

Cisco IOS: 12.2(6)i1, 12.2(58)ex, 12.2(58)ey, 12.2(58)ey1, 12.2(58)ey2, 12.2(58)ez (+1171)
Cisco IOS XE: 3.2.0se, 3.2.1se, 3.2.2se, 3.2.3se, 3.2se, 3.3.0se (+413)

References

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