Inf0s3c Stealer is a sophisticated Python-based malware designed primarily for data theft and system reconnaissance on Windows platforms. It collects extensive system information including host identifiers, CPU details, and network configurations, which helps attackers profile the infected environment. The malware captures screenshots and enumerates running processes and directory structures to gather further intelligence. It targets sensitive user data such as passwords, cookies, browsing history, and cryptocurrency wallets, consolidating stolen data into a password-protected archive for exfiltration. Persistence is achieved through injection into the Discord application and manipulation of Windows Startup entries, enabling the malware to survive reboots and maintain a foothold. Anti-virtual machine (anti-VM) checks are implemented to evade analysis in sandboxed or virtualized environments, and the malware can self-delete after execution to reduce forensic traces. The use of UPX packing and PyInstaller packaging techniques complicates detection and analysis. The malware leverages multiple Windows API calls and employs various MITRE ATT&CK techniques such as process injection (T1055), credential dumping (T1003), system information discovery (T1082), and data exfiltration over command and control channels (T1071). Similarities with other malware projects suggest that Inf0s3c Stealer could be rapidly iterated and widely distributed, posing a persistent threat. No known exploits in the wild or specific threat actors have been identified yet, but the malware’s capabilities indicate a medium severity threat with significant potential for data compromise and operational disruption.

For European organizations, the Inf0s3c Stealer presents a considerable risk to confidentiality and integrity of sensitive data. The theft of credentials, cookies, and browsing history can lead to unauthorized access to corporate accounts, financial systems, and intellectual property. Cryptocurrency wallets targeted by the malware pose direct financial risks. The persistence mechanisms and anti-VM techniques complicate detection and removal, potentially allowing prolonged unauthorized access. Organizations relying on Discord for communication may be particularly vulnerable due to the malware’s injection technique. The self-deletion feature hinders incident response and forensic investigations, increasing the likelihood of undetected breaches. The malware’s ability to gather system and network information also facilitates lateral movement and further exploitation within corporate networks. This threat could disrupt business operations, cause financial losses, and damage reputations, especially in sectors with high-value data such as finance, technology, and critical infrastructure. Given the malware’s Python base and use of common Windows APIs, it can affect a broad range of Windows systems across Europe, including endpoints and servers.

European organizations should implement targeted defenses beyond generic advice. First, deploy advanced endpoint detection and response (EDR) solutions capable of detecting process injection, suspicious startup modifications, and unusual Discord process behaviors. Monitor for UPX-packed binaries and PyInstaller artifacts as indicators of potential Inf0s3c Stealer presence. Enforce strict application whitelisting and restrict execution of unauthorized Python scripts or executables. Harden Discord client usage by limiting permissions and monitoring for injection attempts. Implement network segmentation to limit lateral movement and monitor outbound traffic for anomalous data exfiltration patterns, especially encrypted archives. Employ multi-factor authentication (MFA) to mitigate risks from stolen credentials. Regularly audit Windows startup entries and running processes for unauthorized changes. Use sandbox evasion detection tools to identify anti-VM behaviors. Conduct user awareness training focused on phishing and social engineering, common infection vectors for stealers. Finally, maintain robust backup and incident response plans to recover from potential data loss or ransomware follow-on attacks.