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Iranian hackers target over 100 organizations in government espionage operation

Written by Gugu Ntsele | October 25, 2025

MuddyWater, an Iranian nation-state threat group, has launched an espionage campaign targeting over 100 organizations across the Middle East and North Africa, using a compromised email account to distribute the Phoenix backdoor for intelligence gathering operations.

 

What happened

Singaporean cybersecurity experts published a technical report revealing that MuddyWater has been conducting a targeted campaign against organizations in the MENA region. The threat actor compromised an email account and used NordVPN to access it, then distributed phishing emails that appeared to be legitimate correspondence. The campaign primarily targeted government entities, with more than three-fourths of victims being embassies, diplomatic missions, foreign affairs ministries, and consulates. Additional targets included international organizations and telecommunications firms. The attackers distributed weaponized Microsoft Word documents that prompted recipients to enable macros. Once enabled, malicious Visual Basic for Application (VBA) code executed, deploying version 4 of the Phoenix backdoor through a loader called FakeUpdate.

 

The backstory

MuddyWater, also known by multiple aliases including Boggy Serpens, Cobalt Ulster, Mango Sandstorm, and Seedworm, is assessed to be affiliated with Iran's Ministry of Intelligence and Security (MOIS). The threat actor has been active since at least 2017. Group-IB first documented MuddyWater's use of Phoenix last month, identifying it as a lightweight version of BugSleep, a Python-based implant previously linked to the group. MuddyWater has a documented history of distributing remote access software through phishing campaigns over the years, consistently evolving their tools and techniques to maintain operational effectiveness.

 

Going deeper

The attack chain involves several technical components:

  • Weaponized Microsoft Word documents serve as the initial infection vector
  • Malicious VBA code within the documents deploys a loader called FakeUpdate
  • FakeUpdate contains an AES-encrypted Phoenix payload that it decodes and writes to disk
  • Two Phoenix variants (Version 3 and Version 4) have been detected in the wild
  • Phoenix offers capabilities including system information gathering, persistence establishment, interactive shell launching, and file upload/download functionality
  • The attacker's command-and-control server (159.198.36[.]115) also hosts remote monitoring and management (RMM) utilities and a custom web browser credential stealer targeting Brave, Google Chrome, Microsoft Edge, and Opera

What was said

According to security researchers, "MuddyWater accessed the compromised mailbox through NordVPN (a legitimate service abused by the threat actor), and used it to send phishing emails that appeared to be authentic correspondence."

They further explained that "By exploiting the trust and authority associated with such communications, the campaign significantly increased its chances of deceiving recipients into opening the malicious attachments."

The researchers concluded that "By deploying updated malware variants such as the Phoenix v4 backdoor, the FakeUpdate injector, and custom credential-stealing tools alongside legitimate RMM utilities like PDQ and Action1, MuddyWater demonstrated an enhanced ability to integrate custom code with commercial tools for improved stealth and persistence."

 

In the know

Nation-state threat actors are government-sponsored hacking groups that conduct cyber espionage operations to gather intelligence for their countries. These groups normally target government entities, diplomatic missions, and critical infrastructure to steal sensitive information, monitor communications, and maintain long-term access to compromised networks. Unlike cybercriminals motivated by financial gain, nation-state actors focus on strategic intelligence collection and geopolitical objectives. They often use techniques and custom malware, frequently abusing legitimate tools and services to evade detection. Understanding nation-state threats is important for organizations in sensitive sectors, as these actors possess resources and persistence in pursuing their targets.

 

Why it matters

This campaign shows the ongoing threat faced by government and diplomatic entities in the MENA region from Iranian intelligence operations. The use of a compromised legitimate email account to distribute malware shows how nation-state actors exploit trusted communication channels to bypass security awareness training and email filters. For organizations in the targeted sectors, this represents a danger to sensitive diplomatic communications and classified information. 

 

The bottom line

Organizations in government, diplomatic, and telecommunications sectors must implement email security measures and employee training to defend against nation-state phishing campaigns. Disabling macros by default, implementing strict email authentication protocols, and monitoring for suspicious use of legitimate remote access tools are essential steps. Given MuddyWater's documented persistence and changing tactics, maintaining vigilance and updating security controls regularly is a must for protecting sensitive information from Iranian intelligence gathering operations.

 

FAQs

What is the Phoenix backdoor, and how does it differ from other malware used by MuddyWater?

Phoenix is a lightweight malware implant designed for intelligence gathering, offering stealth and persistence features compared to MuddyWater’s earlier, heavier tools.

 

How did the attackers manage to make their phishing emails look legitimate?

They used a compromised government-associated email account, allowing them to send messages that appeared authentic.

 

Why did MuddyWater choose to target diplomatic and government entities specifically?

These targets offer valuable geopolitical intelligence that supports Iran’s national strategic objectives.

 

What role did NordVPN play in this campaign?

NordVPN was misused to conceal the attackers’ identities and locations while accessing the compromised mailbox.

 

What security weaknesses allowed this campaign to succeed?

The success relies on human error, specifically, users enabling macros in malicious Word documents.