CVE-2025-20333

2026-05-134 minCanadian Centre for Cyber Securitycritical

The Canadian Centre for Cyber Security released a daily digest highlighting critical vulnerabilities across Cisco, IBM, Dell, Ubuntu, and various ICS platforms. Notably, Cisco ASA and FTD devices are affected by a newly identified persistence mechanism known as the FIRESTARTER backdoor, which survives previous patches for CVE-2025-20333, CVE-2025-20362, and CVE-2025-20363.

2026-05-135 minCISAcritical

CISA and NCSC identified FIRESTARTER, a persistent Linux ELF backdoor deployed by APT actors on Cisco Firepower and Secure Firewall devices. The malware hooks into the LINA engine, survives firmware updates and soft reboots, and facilitates the deployment of secondary payloads like LINE VIPER to establish unauthorized VPN sessions.