Researchers Detect ZionSiphon Malware Targeting Israeli Water, Desalination OT Systems

Cybersecurity researchers have flagged a new malware called ZionSiphon that appears to be specifically designed to target Israeli water treatment and desalination systems.

The malware has been codenamed ZionSiphon by Darktrace, highlighting its ability to set up persistence, tamper with local configuration files, and scan for operational technology (OT)-relevant services on the local subnet. According to details on VirusTotal, the sample was first detected in the wild on June 29, 2025, right after the Twelve-Day War between Iran and Israel that took place between June 13 and 24.

"The malware combines privilege escalation, persistence, USB propagation, and ICS scanning with sabotage capabilities aimed at chlorine and pressure controls, highlighting growing experimentation with politically motivated critical infrastructure attacks against industrial operational technologies globally," the company said.

ZionSiphon, currently in an unfinished state, is characterized by its Israel-focused targeting, going after a specific set of IPv4 address ranges that are located within Israel -

• 2.52.0[.]0 - 2.55.255[.]255
• 79.176.0[.]0 - 79.191.255[.]255
• 212.150.0[.]0 - 212.150.255[.]255

Besides encoding political messages that claim support for Iran, Palestine, and Yemen, the malware embeds Israel-linked strings in its target list that correspond to the nation's water and desalination infrastructure. It also includes checks to ensure that in those specific systems.

"The intended logic is clear: the payload activates only when both a geographic condition and an environment-specific condition related to desalination or water treatment are met," the cybersecurity company said.

Once launched, ZionSiphon identifies and probes devices on the local subnet, attempts protocol-specific communication using Modbus, DNP3, and S7comm protocols, and modifies local configuration files by tampering with parameters associated with chlorine doses and pressure. An analysis of the artifact has found the Modus-oriented attack path to be the most developed, with the remaining two only including partially functional code, indicating that the malware is still likely in development.

A notable aspect of the malware is its ability to propagate the infection over removable media. On hosts that do not meet the criteria, it initiates a self-destruct sequence to delete itself.

"Although the file contains sabotage, scanning, and propagation functions, the current sample appears unable to satisfy its own target-country checking function even when the reported IP falls within the specified ranges," Darktrace said. "This behavior suggests that the version is either intentionally disabled, incorrectly configured, or left in an unfinished state."

"Despite these limitations, the overall structure of the code likely indicates a threat actor experimenting with multi‑protocol OT manipulation, persistence within operational networks, and removable‑media propagation techniques reminiscent of earlier ICS‑targeting campaigns."

The disclosure coincides with the discovery of a Node.js-based implant called RoadK1ll that's designed to maintain reliable access to a compromised network while blending into normal network activity.

"RoadK1ll is a Node.js-based reverse tunneling implant that establishes an outbound WebSocket connection to attacker-controlled infrastructure and uses that connection to broker TCP traffic on demand," Blackpoint Cyber said.

Last week, Gen Digital also took the wraps off a virtual machine (VM)-obfuscated backdoor dubbed AngrySpark. It operates as a three-stage system, using a DLL masquerading as a Windows component to inject shellcode into svchost.exe, establishing stealthy persistence and a command-and-control channel that flies under the radar.