CVE-2026-20185 Cisco SG350 and SG350X Series Managed Switches SNMP Denial of Service Vunerability
An authenticated remote attacker can cause a denial of service on Cisco SG350 switches by sending a malicious SNMP request, requiring valid credentials.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-20185?
CVE-2026-20185 is a high-severity denial of service vulnerability in Cisco Small Business Smart and Managed Switches, published on 6 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco 350 Series Managed Switches (SG350) and Cisco 350X Series Stackable Managed Switches (SG350X) firmware could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper error handling when parsing response data for a specific SNMP request. An attacker could exploit this vulnerability by sending a specific SNMP request to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly, resulting in a DoS condition. This vulnerability affects SNMP versions 1, 2c, and 3. To exploit this vulnerability through SNMPv2c or earlier, the attacker must know a valid read-write or read-only SNMP community string for the affected system. To exploit this vulnerability through SNMPv3, the attacker must have valid SNMP user credentials for the affected system.
Weakness: CWE-122
Which versions are affected by CVE-2026-20185?
How do I fix CVE-2026-20185?
No fix has been published for CVE-2026-20185 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-20185 being exploited?
There is no known exploitation of CVE-2026-20185 in the wild and no public exploit code.
Sources
Also known as GHSA-7rq4-mv4g-6vcp.