Cybersecurity briefing — 2026-04-24

If you patched your Cisco firewalls and called it done, you may want to look again.

• Firestarter backdoor persists on Cisco Firepower and Secure Firewall
• iPhone Notification Cache Exposed Deleted Signal Messages
• Worm-like npm malware steals tokens and republished packages
• China-Nexus Botnets Turn Everyday Devices Into Cover
• GopherWhisper Turns Collaboration Tools Into Espionage Channels
• Industry and Pentagon Face Security Risks from Agentic AI Adoption
• AI Code and Prompt Injection Expand the Attack Surface
• WordPress Cache Plugin Lets Attackers Upload Files
• Trusted Bitwarden CLI Release Turned Secret Harvester
• LMDeploy SSRF Opens Cloud Metadata in Hours
• SentinelOne identifies Fast16 Lua-based sabotage malware predating Stuxnet
• Passkeys Become the Default Login Standard
• AI Agents Can Now Chain Cloud Breaches Alone
• Rituals Member Data Downloaded in Breach
• AI Speeds Discovery, But Governance Becomes the Bottleneck
• Vercel Breach Exposes Customer Secrets Risk
• macOS Users Become the Weak Link in Fake Updates
• SilentGlass Targets a Neglected Monitor Attack Path