Hazard

Is CVE-2025-20352 being exploited?

Confirmed exploited in the wild

CISA has evidence of active exploitation. This is not theoretical risk — someone has already used it against someone.

Cisco IOS and IOS XE Software SNMP Denial of Service and Remote Code Execution Vulnerability

Cisco · IOS and IOS XE

CVSS 7.7 EPSS 39% no public exploit indexed Fix deadline passed 20 October 2025

What it is

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.

Why we say that

  • CISA's federal remediation deadline (2025-10-20) has passed
  • Listed in the CISA Known Exploited Vulnerabilities catalogue

Every line above comes from a named public source. Where the evidence is thin, we say so rather than inventing confidence — see methodology.

What to do

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

What it costs when this goes wrong

This is where UK enforcement meets the vulnerability record. Where an unfixed vulnerability leads to a breach, the ICO treats it as a security failure under UK GDPR. Recent cases:

All UK cases caused by unpatched software →