Cisco SG350/SG350X SNMP DoS Vulnerability Advisory (cisco-sa-sg350-snmp-dos-0EF2ZT)

Vulnerability Overview Vulnerability Name: Cisco SG350 and SG350X Series Managed Switches SNMP Denial of Service Vulnerability Vulnerability ID: cisco-sa-sg350-snmp-dos-0EF2ZT Release Date: May 6, 2026 CVSS Score: 7.7 Vulnerability Type: Denial of Service (DoS) Vulnerability Description: This vulnerability exists in the Simple Network Management Protocol (SNMP) subsystem of Cisco 350 Series Managed Switches (SG350) and Cisco 350X Series Stacked Managed Switches (SG350X). An attacker can exploit the error handling mechanism by sending specific SNMP requests, causing the device to unexpectedly reboot and resulting in a denial of service. Affected Products Affected Products: - SG350-28P Switch - SG350-28MP Switch - SG350-52P Switch - SG350-52MP Switch - SG350X Series Switches Affected Versions: SNMPv1, SNMPv2c, and SNMPv3 Prerequisites: - The device has SNMPv1 or SNMPv2c enabled, and the attacker must know a valid read-write or read-only SNMP community string. - The device has SNMPv3 enabled, and the attacker must know valid SNMP user credentials. - The device must have two or more 60-watt PoE ports. Remediation Current Status: As the affected products are out of maintenance, Cisco has not released a software update. Mitigation Measures: 1. Disable Vulnerable Object Identifiers (OIDs): - Create a new SNMP view that excludes the affected OIDs. - Apply this view to all configured SNMP community strings or SNMPv3 user groups. 2. Specific Command Examples: - For SNMPv1 or SNMPv2c: - For SNMPv3: Additional Information No Known Workarounds: There are currently no known workarounds to fully resolve this vulnerability. Recommendation: Customers should regularly consult Cisco Security Advisories to determine exposure and complete upgrade solutions. If information is unclear, it is recommended to contact the Cisco Technical Assistance Center (TAC) or your contract maintenance provider. Source Acknowledgments: Cisco thanks security researcher Ryan Moore for reporting this vulnerability. Revision History Version 1.0: Initial public release, final status, released on May 6, 2026.

Goal Reached Thanks to every supporter — we hit 100%!

Cisco SG350/SG350X SNMP DoS Vulnerability Advisory (cisco-sa-sg350-snmp-dos-0EF2ZT)