CVE-2020-3235: Cisco IOS and IOS XE Software Simple Network Management Protocol Denial of Service Vulnerability

Severity: high (CVSS 7.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% 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-118

Description

A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS Software and Cisco IOS XE Software on Catalyst 4500 Series Switches could allow an authenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient input validation when the software processes specific SNMP object identifiers. An attacker could exploit this vulnerability by sending a crafted SNMP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: To exploit this vulnerability by using SNMPv2c or earlier, the attacker must know the SNMP read-only community string for an affected system. To exploit this vulnerability by using SNMPv3, the attacker must know the user credentials for the affected system.

Affected products

Cisco IOS: 12.2(52)sg, 12.2(53)sg1, 12.2(53)sg2, 12.2(53)sg3, 12.2(53)sg4, 12.2(53)sg5 (+76)
Cisco IOS XE: 3.2.0sg, 3.2.1sg, 3.2.2sg, 3.2.3sg, 3.2.4sg, 3.2.5sg (+62)
Oracle Goldengate Management Pack: 12.2.1.2.0

References

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