MalwarePublished 5 Feb 2026

Malicious Script Delivering More Maliciousness, (Wed, Feb 4th)

Source SANS ISC Handlers Diary

Description

A malicious email attachment containing a . bat script is delivering a multi-stage malware payload designed to steal data via a Chrome injector. The initial script is a fork of publicly available GitHub code but includes obfuscated Base64-encoded payloads executed through PowerShell. The payload fetches additional components from a compromised website, including a . NET program that establishes persistence via scheduled tasks and communicates with a Telegram-based command and control (C2) server. This malware, identified as XWorm V7.x, uses sophisticated obfuscation and evasion techniques to avoid detection. It targets Windows systems and aims to steal sensitive information silently. The attack does not require user interaction beyond opening the malicious attachment and does not currently have known widespread exploitation but poses a medium risk. European organizations using Windows and Chrome browsers are potential targets, especially those with less mature email security controls.

Impact

For European organizations, this malware poses a significant risk to confidentiality as it is designed to steal sensitive data through Chrome injection. The persistence mechanism ensures long-term presence on infected systems, increasing the likelihood of data exfiltration. The use of Telegram as a C2 channel complicates detection and blocking efforts due to the legitimate nature of the Telegram API. Organizations with Windows 10 Pro endpoints and Chrome browsers are particularly vulnerable. The malware could lead to credential theft, intellectual property loss, and potential lateral movement within networks. The stealthy nature and obfuscation techniques reduce the chance of early detection, increasing potential damage. Sectors with high-value data such as finance, healthcare, and government could face targeted attacks. Additionally, the infection vector via email attachments highlights the risk of phishing campaigns exploiting human factors. The medium severity rating reflects the balance between the complexity of exploitation and the potential impact on data confidentiality and operational integrity.

Defensive guidance

European organizations should implement advanced email filtering solutions capable of detecting obfuscated scripts and malicious attachments, including sandboxing and behavioral analysis. Endpoint detection and response (EDR) tools should be configured to monitor for suspicious scheduled tasks, especially those named similarly to legitimate applications (e.g., "Chromiumx2"). PowerShell logging and script block logging should be enabled to detect unusual decoding and execution patterns. Network monitoring should include filtering and anomaly detection for Telegram API traffic, particularly outbound requests to known malicious bot tokens or suspicious chat IDs. User awareness training must emphasize the risks of opening unexpected email attachments, even if they appear legitimate. Regular patching of Windows and Chrome browsers is essential to reduce exploitation of known vulnerabilities. Restricting execution of .bat files and PowerShell scripts from email attachments through application whitelisting or controlled folder access can reduce infection risk. Incident response plans should include procedures for identifying and removing XWorm infections and analyzing persistence mechanisms. Finally, organizations should maintain threat intelligence sharing with European cybersecurity communities to stay updated on evolving XWorm variants.

References

isc.sans.edu/diary/rss/32682 (opens in a new tab)

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Description

AI analysisMachine-generated, updated 11 Feb 2026, 12:18 UTC

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