SideWinder APT: A Deep Dive into the Advanced Tactics and Techniques of a State-Sponsored Threat Actor

Introduction

SideWinder APT, also known as Razor Tiger, Rattlesnake, and T-APT-04, is a suspected Indian state-sponsored threat actor group that has been active since at least 2012. The group primarily targets government, military, and business entities throughout Asia, with a focus on Pakistan, China, Nepal, and Afghanistan. SideWinder has been involved in numerous operations targeting other countries in the region, including Bangladesh, Myanmar, Qatar, Sri Lanka, and Myanmar. In this blog post, we will explore the advanced tactics and techniques employed by SideWinder APT, as well as provide recommendations for defense against their attacks.

Advanced Tactics and Techniques

SideWinder APT employs a variety of advanced tactics and techniques to infiltrate their targets and avoid detection. Some of these tactics include:

1. Email spear-phishing: SideWinder uses targeted spear-phishing emails to deliver malicious attachments or URLs to potential victims. These emails are often crafted to appear as if they come from legitimate sources, increasing the likelihood that the recipient will open the attachment or click on the link.
2. Document exploitation: The group uses weaponized documents, such as RTF files, to deliver their malware payloads. These documents often contain exploits for known vulnerabilities, such as CVE-2017-0199, which allows the attackers to execute their payloads without the need for user interaction.
3. DLL side-loading: SideWinder employs DLL side-loading techniques to execute their malicious payloads. This involves hijacking the way Windows loads DLL (Dynamic Link Library) files, allowing the attackers to load their malicious DLLs alongside legitimate applications. In some cases, the group has been observed using “double DLL sideloading” to further obfuscate their activities and evade detection.
4. Server-based polymorphism: The group has been known to use server-based polymorphism techniques to deliver next-stage payloads. This involves changing the characteristics of their malware on the server-side, making it more difficult for traditional signature-based antivirus solutions to detect the malicious files.
5. Custom tools: SideWinder has developed custom tools, such as SideWinder.AntiBot.Script, to redirect victims for downloading initial files from infected websites. This tool has been used in previously undocumented phishing attacks against Pakistani organizations.
6. Mobile malware: The group has also been observed using malicious Android apps to compromise devices and collect user data. One such app, called Camero, exploits the CVE-2019-2215 vulnerability in Binder, marking the first instance of this exploit being used in the wild.

Targets and Campaigns

SideWinder has targeted various Southeast Asian entities, including those in Pakistan, Afghanistan, Bhutan, China, Myanmar, Nepal, and Sri Lanka. The group has launched more than 1,000 attacks since April 2020, indicating a newfound aggression since it commenced operations in 2012. Some notable campaigns include:

• Compromising the official website of Pakistan’s National Electric Power Regulatory Authority (NEPRA) to deliver the WarHawk malware.
• Targeting Pakistan government organizations using server-based polymorphism techniques.
• A series of phishing campaigns between June and November 2021 targeting organizations in Afghanistan, Bhutan, Myanmar, Nepal, and Sri Lanka.

Recommendations for Defense

To defend against SideWinder APT attacks, organizations should consider the following recommendations:

1. Keep software up to date: Ensure that your operating system and all software are up to date with the latest security patches.
2. Implement strong email security measures: Use email filtering and authentication to protect against phishing attacks.
3. Educate employees about phishing and social engineering: Train employees to recognize and report suspicious emails and other potential attack vectors.
4. Use application whitelisting and firewall rules: Harden applications to help prevent additional malicious malware modules from SideWinder’s servers.
5. Monitor network traffic: Regularly analyze network traffic for signs of malicious activity and potential indicators of compromise.

By following these recommendations, organizations can reduce their risk of falling victim to SideWinder APT attacks and better protect their sensitive information and systems.