Wednesday, May 14, 2025
HomeCyber Security NewsSidewinder Hacker Group Using Weaponized Documents to Deliver Malware

Sidewinder Hacker Group Using Weaponized Documents to Deliver Malware

Published on

SIEM as a Service

Follow Us on Google News

Sidewinder APT group’s sophisticated threat landscape reveals a skilled and persistent threat targeting the Nepalese Government entities. 

Their focus extends to South Asian governments, with researchers also identifying a recent complex attack on Bhutan.

Cybersecurity researchers at Cyfirma recently identified that the operators of the Sidewinder hacker group are actively using weaponized documents to deliver backdoors.

- Advertisement - Google News

Here below we have mentioned all the other names of the Sidewinder APT group:-

  • Rattlesnake
  • Hardcore Nationalist
  • HN2
  • APT Q4
  • RAZOR Tiger
  • APT Q39
  • BabyElephant
  • GroupA21

Sidewinder Hacker Group

Using decoy documents resembling Nepalese Prime Minister’s Office communications, the group employs advanced tactics like email spear-phishing and malicious macros. 

That’s why urgent attention and coordinated action from the stakeholders are crucial.

In the main payload “conhost.exe” (Nim Backdoor), all the URLs are hardcoded, and they are settled to the following IP address:-

  • 213[.]109[.]192[.]93

Here below, we have mentioned all the URLs:-

  • http[:]//mail[.]mofa[.]govnp[.]org/mail/AFA/
  • http[:]//nitc[.]govnp[.]org/mail/AFA/
  • http[:]//dns[.]govnp[.]org/mail/AFA/
  • http[:]//mx1[.]Nepal[.]govnp[.]org/mail/AFA/

Spear-phished email delivers a malicious document, triggering an embedded macro upon opening. The victim is manipulated as the document prompts them to enable editing.

Malicious document
Malicious document (Source – Cyfirma)

The deceptive content hints at targeting Nepalese government officials. The document’s embedded macro, part of a multi-stage attack, establishes persistence and executes payloads. 

The opening of the document triggers the macro and creates a VBScript file for persistence. It introduces delays and checks internet connectivity before executing encoded batch files. 

The batch script directs the execution of VBScript and other batch files, creating scheduled tasks and self-deleting files. Functions like read_shell write binary data to a file, while hide_cons hide the console window. 

The vb_chain function coordinates various actions, including creating and executing scripts and scheduling tasks to establish a chain of events on the infected system.

The VBScript file unzFile.vbs extracts contents from conhost.zip. The following batch file executes scripts, creates tasks, and handles cleanup:-

  • 2L7uuZQboJBhTERK.bat
  • 2BYretPBD4iSQKYS.bat
  • d.bat
  • e.bat 

The macro exhibits advanced evasion with obfuscation by leveraging the following elements:-

  • VBScript
  • Batch files
  • Scheduled tasks

Besides this, its multi-stage execution makes the complete analysis more challenging and complex. 

Enabling macros triggers the deployment of scripts and the Nim backdoor-like conhost.exe. This executable aims to connect to the threat actors’ C2 server for unauthorized access, indicating an ongoing campaign since September.

The reverse shell sample enables threat actor access through a reverse shell, providing control over the compromised system. Trojan.khalesi obstructs dynamic analysis, detecting and exiting if tools are found. 

The binary targets various monitoring and analysis tools. The process tree reveals the periodic use of cmd.exe to execute tasklist.exe, which is likely for information gathering or system monitoring.

.exe files
.exe files (Source – Cyfirma)

Recommendations

Here below, we have mentioned all the recommendations provided by the security analysts:-

  • Use robust endpoint security.
  • Employ reputable antivirus and anti-malware.
  • Regularly update OS, applications, and security software.
  • Segregate the network into segments.
  • Educate and train employees on phishing and social engineering dangers.
  • Configure firewalls to block outbound communication.
  • Deploy behavior-based monitoring.
  • Establish application whitelisting policies.
  • Monitor network traffic closely.
  • Create a comprehensive incident response plan.
  • Stay updated on threat intelligence and IOCs.
  • Maintain regular backups of critical data.
  • Implement safeguarding measures.
  • Restrict user permissions.

IOCs

IOCs
IOCs (Source – Cyfirma)
Tushar Subhra
Tushar Subhra
Tushar is a Cyber security content editor with a passion for creating captivating and informative content. With years of experience under his belt in Cyber Security, he is covering Cyber Security News, technology and other news.

Latest articles

Threat Actors Leverage Weaponized HTML Files to Deliver Horabot Malware

A recent discovery by FortiGuard Labs has unveiled a cunning phishing campaign orchestrated by...

TA406 Hackers Target Government Entities to Steal Login Credentials

The North Korean state-sponsored threat actor TA406, also tracked as Opal Sleet and Konni,...

Google Threat Intelligence Releases Actionable Threat Hunting Technique for Malicious .desktop Files

Google Threat Intelligence has unveiled a series of sophisticated threat hunting techniques to detect...

New Adobe Photoshop Vulnerability Enables Arbitrary Code Execution

Adobe has released critical security updates addressing three high-severity vulnerabilities (CVE-2025-30324, CVE-2025-30325, CVE-2025-30326) in...

Resilience at Scale

Why Application Security is Non-Negotiable

The resilience of your digital infrastructure directly impacts your ability to scale. And yet, application security remains a critical weak link for most organizations.

Application Security is no longer just a defensive play—it’s the cornerstone of cyber resilience and sustainable growth. In this webinar, Karthik Krishnamoorthy (CTO of Indusface) and Phani Deepak Akella (VP of Marketing – Indusface), will share how AI-powered application security can help organizations build resilience by

Discussion points


Protecting at internet scale using AI and behavioral-based DDoS & bot mitigation.
Autonomously discovering external assets and remediating vulnerabilities within 72 hours, enabling secure, confident scaling.
Ensuring 100% application availability through platforms architected for failure resilience.
Eliminating silos with real-time correlation between attack surface and active threats for rapid, accurate mitigation

More like this

Threat Actors Leverage Weaponized HTML Files to Deliver Horabot Malware

A recent discovery by FortiGuard Labs has unveiled a cunning phishing campaign orchestrated by...

TA406 Hackers Target Government Entities to Steal Login Credentials

The North Korean state-sponsored threat actor TA406, also tracked as Opal Sleet and Konni,...

Google Threat Intelligence Releases Actionable Threat Hunting Technique for Malicious .desktop Files

Google Threat Intelligence has unveiled a series of sophisticated threat hunting techniques to detect...