Cisco IOS and IOS XE contains a stack-based buffer overflow vulnerability in the Simple Network Management Protocol (SNMP) subsystem that could allow for denial of service or remote code execution. A successful exploit could allow a low-privileged attacker to cause the affected system to reload, resulting in a DoS condition, or allow a high-privileged attacker to execute arbitrary code as the root user and obtain full control of the affected system.
Cisco · IOS and IOS XE
Known ransomware use: Unknown
Follow the source advisory and validate exposure in your environment.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Recent reporting that mentions CVE-2025-20352.
Threat actors exploited a recently patched remote code execution vulnerability (CVE-2025-20352) in older, unprotected Cisco networking devices to deploy a Linux rootkit and gain persistent access. [...]
Trend™ Research has uncovered an attack campaign exploiting the Cisco SNMP vulnerability CVE-2025-20352, allowing remote code execution and rootkit deployment on unprotected devices, with impacts observed on Cisco 9400, 9300, and legacy 3750G series.