Cisco says Chinese hackers are exploiting its customers with a new zero-day

• A zero-day in Cisco AsyncOS lets attackers gain root access on secure email appliances with spam quarantine exposed online
• All AsyncOS releases are vulnerable, and without an available patch, Cisco urges full wipes and rebuilds to remove persistence
• Researchers suspect a Chinese state-sponsored actor with many large organizations potentially at risk

Cisco warns that some of its products have a zero-day vulnerability that is now being actively exploited in attacks. There is currently no patch available and users are advised to take certain steps to harden their defenses instead.

In a security advisory, Cisco said it became aware of a new cyber attack campaign on December 10. This attack targets appliances running Cisco AsyncOS Software for Cisco Secure Email Gateway and Cisco Secure Email and Web Manager.