Between December 2024 and January 2025, Recorded Future’s Insikt Group identified a campaign exploiting unpatched internet-facing Cisco network devices primarily associated with global telecommunications providers. Victim organizations included a United States-based affiliate of a United Kingdom-based telecommunications provider and a South African telecommunications provider. Insikt Group attributes this activity to the Chinese state-sponsored threat activity group tracked by Insikt Group as RedMike, which aligns with the Microsoft-named group Salt Typhoon. Using Recorded Future® Network Intelligence, Insikt Group observed RedMike target and exploit unpatched Cisco network devices vulnerable to CVE-2023-20198, a privilege escalation vulnerability found in the web user interface (UI) feature in Cisco IOS XE software, for initial access before exploiting an associated privilege escalation vulnerability, CVE-2023-20273, to gain root privileges. RedMike reconfigures the device, adding a generic routing encapsulation (GRE) tunnel for persistent access.

Cisco disclosed a new high-severity zero-day (CVE-2023-20273) today, actively exploited to deploy malicious implants on IOS XE devices compromised using the CVE-2023-20198 zero-day unveiled earlier this week.