Atomic Arch is a major AUR supply-chain attack (over 1.5K packages affected as of now) where attackers hijacked orphaned Arch packages and used malicious install hooks to pull npm payloads that executed a Linux ELF infostealer. It targeted developer secrets like SSH keys, GitHub/npm tokens, browser sessions, Docker/Vault credentials, and chat app data, while also using an eBPF rootkit to hide itself when run as root.