Hackers Deploy Linux Rootkits via Cisco SNMP Flaw in “Zero Disco’ Attacks
Details of a new campaign that used a recently discovered security hole in Cisco IOS and IOS XE software to install Linux rootkits on older, unprotected computers have been made public by cybersecurity researchers.
CVE-2025-20352 (CVSS score: 7.7) is a stack overflow vulnerability in the Simple Network Management Protocol (SNMP) subsystem that could be weaponized to enable an authenticated, remote attacker to execute arbitrary code by sending crafted SNMP packets to a vulnerable device. Trend Micro has codenamed this activity Operation Zero Disco. No known threat actor or group has been implicated in the intrusions.
Cisco fixed the vulnerability late last month, but not before real-world assaults took advantage of it as a zero-day vulnerability.
According to researchers Dove Chiu...

