CVE-2025-20393 Exploitation: A Maximum-Severity Zero-Day Vulnerability in Cisco AsyncOS Software Abused in Attacks by the China-Backed APT UAT-9686  | SOC Prime

As 2025 draws to a close, yet another critical Cisco zero-day has emerged, joining earlier high-severity disclosures: two RCE flaws in Cisco ISE and SE-PIC (CVE-2025-20281 and CVE-2025-20282) and a September zero-day in Cisco IOS and IOS XE (CVE-2025-20352). The latest uncovered Cisco vulnerability, identified as CVE-2025-20393, affects AsyncOS Software and reaches a maximum-severity CVSS score of 10.0. The flaw is already under active exploitation by a China-linked APT group tracked as UAT-9686.  

Exploitation of zero-day vulnerabilities is increasing, while the time to patch them is shrinking, making prompt updates more critical than ever. The 2025 Verizon DBIR report highlights a 34% year-over-year rise in breaches initiated via vulnerability exploitation, highlighting the need for proactive defenses. China-backed espionage campaigns are driving this trend, with operations increasingly emphasizing stealth and operational security over the…