CVE-2026-20124

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.

• CWE-772

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-snmp-dos-ZAqNm4MDMitigation, Vendor Advisory

Published

Aug 5, 2026

Last Modified

Sep 17, 2026

Status

Analyzed

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2026-20119A vulnerability in the text rendering subsystem of Cisco Tel…7.5
• CVE-2026-2012A vulnerability was determined in itsourcecode Student Manag…9.8
• CVE-2026-20120A vulnerability in the access control list (ACL) Object Grou…5.8
• CVE-2026-20121A vulnerability in the access control list (ACL) Object Grou…5.3
• CVE-2026-20122A vulnerability in the API of Cisco Catalyst SD-WAN Manager …5.4
• CVE-2026-20123A vulnerability in the web-based management interface of Cis…6.1
• CVE-2026-20125A vulnerability in the HTTP Server feature of Cisco IOS Soft…7.7
• CVE-2026-20126A vulnerability in Cisco Catalyst SD-WAN Manager could allow…7.8
• CVE-2026-20127A vulnerability in the peering authentication in Cisco Catal…10
• CVE-2026-20128A vulnerability in the Data Collection Agent (DCA) feature o…7.5
• CVE-2026-20129A vulnerability in the API user authentication of Cisco Cata…9.8
• CVE-2026-2013A vulnerability was identified in itsourcecode Student Manag…9.8