New PATCHCORD Backdoor Targets Afghan Telecom and Indian Critical Infrastructure

Afghan telecom providers and South Asian critical infrastructure organizations have emerged as the target of a new ongoing campaign that delivers a previously undocumented backdoor called PATCHCORD.

According to Acronis Threat Research Unit (TRU), the backdoor is a compiled C/C++ implant delivered by means of sector-specific lures, including fake VPN installers impersonating Afghan Telecom (AFTEL) and telecom management tools.

An analysis of the threat actor's infrastructure has also led to the discovery of another Go-based backdoor dubbed SHEETCORD that uses Google Sheets for command-and-control (C2) communications. The malware has been found to be delivered via a domain impersonating India's National Informatics Center (NIC).

"The campaign's infrastructure centers on a single C2 server with multiple associated domains, including domains impersonating Afghan telecom operators and a hijacked legitimate healthcare domain," researchers Darrel Virtusio, Santiago Pontiroli, and Subhajeet Singha said in a report shared with The Hacker News.

The activity is assessed to be the work of a Pakistan-aligned threat actor known as APT36 (aka Transparent Tribe) with moderate confidence, citing overlaps in targeting patterns, malware similarities, shared infrastructure, and operational tradecraft.

The starting point is a ZIP archive named "Telecom_TMS.zip" that contains an Inno Setup installer ("TMS_AfghanTelecom.exe") responsible for delivering PATCHCORD. TMS is short for Transport Management System, an internal system used by Afghan Telecom, a state-owned telecommunications company, to track corporate vehicle and transport requests.

Upon execution, the backdoor conceals its console window, sets up persistence by hijacking browser shortcuts associated with Google Chrome, Microsoft Edge, and Mozilla Firefox after checking it's running with elevated privileges, fingerprints the host, and registers with its C2 server ("46.30.188[.]13") to receive tasking commands that allow it to -

• Adjust C2 beacon interval
• Enumerate all running processes
• Decode and decrypt a shellcode payload received from the C2 server and execute it in memory
• Execute arbitrary commands via "cmd.exe"
• Provide interactive control over the browser shortcut hijacking persistence mechanism

"When launched through a hijacked browser shortcut, it transparently starts the legitimate browser before continuing execution in the background, preserving the expected user experience while maintaining persistence," Acronis said. "Otherwise, it proceeds directly to its primary functionality."

The implant also checks for a Windows Registry value named "BeaconBrowserHijack" under "HKCU\Software\Microsoft\Windows\CurrentVersion\Run." If the value already exists, it skips the shortcut hijacking process, assuming the system has already been compromised.

Should this not be the case, it writes its own executable path to the Windows Registry key and establishes persistence across reboots to activate the browser shortcut hijacking routine whenever the current user logs into Windows.

Further examination of the threat actor infrastructure has uncovered a campaign targeting Indian government IT networks, including a fake website that mimics NIC ("nic-support[.]site") to deploy SHEETCORD, which combines functionality present in SHEETCREEP with those incorporated in PATCHCORD.

The backdoor implements a remote command execution capability through PowerShell instead of "cmd.exe," gathers basic host information, and uses the Windows Startup folder to establish persistence using a Visual Basic Script, packs in PATCHCORD's browser shortcut hijacking mechanism to also target Brave, Opera, and Vivaldi, and uses the Google Sheets API for C2.

PATCHCORD is said to have been put to use by the threat actor since at least March 2026, with one such attack targeting India's energy sector with a variant of the backdoor that features anti-analysis and anti-debugging techniques to sidestep detection.

What's more, an exposed staging server linked to the threat actor has offered insights into their evolving offensive toolkit, including open-source C2 frameworks like antnium, GateSentinel, and SuperShell, exploits for CVE-2024-6387, AI-assisted malware projects, and campaign-specific files.

One such AI-assisted project is HACKERAI C2, which overlaps with PATCHCORD and SHEETCORD but uses GitHub Gists for C2 and implements a dedicated upload and download functionality for both tasking and data exfiltration.

"The campaign reflects an evolution of Transparent Tribe's recent operations," Acronis said. "While the group has historically focused on government, military and diplomatic organizations in India and the broader South Asian region, our investigation identified a stronger operational focus on Afghan telecom providers alongside government, defense and energy organizations."

"Combined with three previously undocumented malware families and the use of Google Sheets and GitHub Gists for C2, the campaign demonstrates continued evolution in both the group's targeting priorities and operational tradecraft."

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