Daily Brief — April 27, 2026

DFIR Daily Threat Brief

💰 Ransomware Activity

In 2026, Qilin remains the most active ransomware group, with February seeing 104 claimed victims. Other notable groups include Medusa and Akira. The rise of Ransomware-as-a-Service continues to fuel growth.

🚨 Critical Vulnerabilities

CVE-2026-20131 in Cisco firewalls and CVE-2026-21902 in Juniper Networks are critical vulnerabilities actively exploited. Both have high CVSS scores and enable remote code execution.

🛡️ Incident Response & DFIR News

Three Microsoft Defender zero-days are actively exploited; CISA added four flaws to its Known Exploited Vulnerabilities catalog with a May 2026 deadline. The FIRESTARTER backdoor targeted a federal Cisco device, surviving patches. NASA employees were duped in a Chinese phishing scheme targeting U.S. defense software.

📰 Latest Ransomware Attacks

In 2026, ransomware attacks remain prevalent, with significant incidents affecting healthcare, manufacturing, and insurance sectors. Notable attacks include breaches by Everest and Anubis ransomware groups. The ransomware landscape shows no signs of slowing down.

Facing an active incident? Contact us immediately at alerts@binary-response.com — we respond 24/7.