Winsage
September 23, 2026
Cisco Talos has disclosed a Windows implant called CLOSEDQUORUM, which automates cyberattack execution using four advanced commercial large language models: DeepSeek, Qwen, Mistral, and Google Gemini. The implant is a 16.4-megabyte executable that conducts reconnaissance on the system and formats the gathered data into prompts for the AI models. Each model votes on one of four actions: steal, inject, persist, or move, with the action receiving the most votes being executed.
When stealing, CLOSEDQUORUM targets three credential stores, dumping LSASS memory and retrieving saved passwords from browsers and cryptocurrency wallets. The stolen data is encrypted and sent to the operator via Discord. For injection, it uses Early Bird APC injection or process hollowing based on model responses. The persist action creates three mechanisms for longevity, including a Registry Run key, a scheduled task, and a WMI event subscription.
CLOSEDQUORUM evades detection by suppressing ETW telemetry and delaying activity to avoid sandbox analyses. It connects to legitimate API endpoints, making blocking ineffective without disrupting enterprise applications. Talos recommends behavioral combination detection strategies and the use of a YARA rule for detection. The CAIRN toolkit has been introduced to detect AI-integrated malware without executing binaries. Unlike previous AI-assisted malware, CLOSEDQUORUM removes human decision-making from the attack process.
