What’s Vulnerable › Vulnerabilities
CVE-2026-20124: Cisco IOS XE Software SNMP Denial of Service Vulnerability
- Severity: high (CVSS 7.7 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.5% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-08-05 · updated 2026-10-23
- Weakness: CWE-772
Description
A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS XE Software could allow an authenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to improper error handling when parsing SNMP requests. This vulnerability affects all versions of SNMP — Versions 1, 2c, and 3. An attacker could exploit this vulnerability by sending a malformed SNMP request to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly. The attacker must have the SNMPv1 or v2c read-only or read-write community string or valid SNMPv3 user credentials on the affected device.
Affected products
- Cisco IOS XE: 3.13.9s, 3.13.10s, 3.16.6bs, 3.16.7as, 3.16.7bs, 3.16.7s (+271)
References
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