Two groups linked to China are exploiting a newly discovered vulnerability in Cisco's email security products. The campaign involves zero-day attacks, highlighting ongoing cybersecurity risks. The issue was reported on December 19, 2025.
Cisco's email security solutions have come under active attack from two Chinese-nexus threat groups. These actors are leveraging a zero-day flaw, meaning the vulnerability was unknown to the company prior to exploitation. Such campaigns underscore the persistent challenges in securing enterprise email systems against sophisticated adversaries.
The exploitation targets products designed to protect against email-based threats, potentially allowing attackers to bypass defenses and deliver malware or steal data. No specific details on the flaw's nature or the exact products affected were disclosed in initial reports, but the involvement of state-linked groups raises concerns about targeted espionage.
Cisco has yet to issue an official response in the available information, though the discovery prompts urgent patching and monitoring recommendations for users. This incident fits into a broader pattern of zero-day abuses by Chinese-affiliated hackers, as seen in previous high-profile breaches.
