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Interlock is a double-extortion ransomware operation active since at least late 2024. It targets enterprise environments in North America and Europe and has been associated with intrusions affecting healthcare, education, government, manufacturing, engineering, construction, and other critical-infrastructure organizations. The operation steals data prior to encryption and pressures victims through leak-site publication threats and regulatory exposure messaging.
Interlock has demonstrated multi-platform ransomware capability, with encryptors reported for Windows and virtualization-oriented environments including VMware ESXi, and broader reporting also linking the group to Linux-targeting activity. Its intrusion tradecraft is multi-stage and adaptable. A frequently observed initial-access method is ClickFix-style social engineering in which fake CAPTCHA or fake-update lures convince a user to paste and execute a command in Windows, leading to PowerShell-based payload retrieval and deployment of remote-access tooling. Interlock has also been linked to exploitation of CVE-2026-20131 in Cisco Secure Firewall Management Center, showing the group can combine social engineering with opportunistic zero-day or edge-device exploitation.
Post-compromise behavior includes reconnaissance, credential access, lateral movement, persistence, defense evasion, data theft, and ransomware deployment. Reported activity includes use of memory acquisition and forensic tooling to extract credential material from RAM, Kerberoasting, NTLM downgrade abuse, creation of scheduled tasks for persistence, tampering with security tools, and movement to domain controllers and hypervisors. Interlock has also used custom remote-access malware families including NodeSnake and InterlockRAT, as well as legitimate remote administration software for redundant access. Additional tooling observed in Interlock-linked operations includes certificate-abuse reconnaissance against Active Directory Certificate Services and proxying or memory-resident backdoor techniques to preserve access and obscure operator infrastructure.
Interlock is commonly characterized as a financially motivated ransomware actor rather than an espionage operator. Reporting has also tracked the cluster under the name GOLD EMBRACE. The group’s operations reflect a mature enterprise-ransomware model that blends credential theft, hands-on-keyboard post-exploitation, exfiltration, and cross-platform encryption to maximize operational disruption and extortion leverage.
Mallory pivots from this family to the IOCs, detections, and named campaigns that touch your stack, and pages you when something new lands.
4 CVEs Mallory has correlated with this family across public research and vendor advisories. Each row links to the full Mallory page for that vulnerability.
More recently, Interlock has been actively exploiting CVE-2026-20131, a critical-severity zero-day vulnerability in Cisco Secure Firewall Management Center (FMC) Software.
PrintNightmare exploit (Interlock staging)
Local privilege escalation exploit CVE-2023-36036 (JunkFiction-crypted) ... CVE CVE-2023-36036 Local privilege escalation exploit used by Interlock and ModeloRAT operators
Interlock ... concealed ... through the custom Hotta Killer evasion tool, which harnesses a zero-day flaw in the legitimate gaming anti-cheat driver GameDriverx64.sys, tracked as CVE-2025-61155, as part of a Bring Your Own Vulnerable Driver attack. ... kernel termination of security software prior to encryption activities.
4 distinct threat actors attributed by public researchers. Open in Mallory to see the full evidence chain and overlapping campaigns.
Interlock ransomware is taking a familiar Windows security tool and using it for credential theft.
The Rhysida and Interlock groups, which are known to attack healthcare and other critical infrastructure, have similar TTPs and encryption binaries, leading to some speculation of a connection between the two groups.
Amazon’s threat intelligence teams have uncovered a new cyber campaign linked to the Interlock ransomware group... The recovered malware and artifacts were attributed to the Interlock ransomware family based on several consistent indicators.
The e-crime group is primarily associated with a wide range of malicious tools, including NodeSnake, Interlock RAT, JunkFiction loader, and Interlock ransomware.
30 distinct techniques documented for this family, organized by ATT&CK tactic.
The agencies said they are aware of Interlock encryptors designed for Windows and Linux operating systems and have observed cyber actors obtaining access using an uncommon method of drive-by download from compromised legitimate websites, among other tactics.
Amazon threat intelligence has identified an active Interlock ransomware campaign exploiting CVE-2026-20131, a critical vulnerability in Cisco Secure Firewall Management Center (FMC) Software that could allow an unauthenticated, remote attacker to execute arbitrary Java code as root on an affected device
The Java variant adds two features... The UpdateThread creates a self-deleting scheduled task... Like the Java variant, the PE uses self-deleting scheduled tasks... A daily scheduled task runs the ransomware at 20:00 as SYSTEM.
A PowerShell-based reconnaissance script systematically collects detailed system and network information, including installed software, running services, browser data, and active connections.
The campaign centers around a flaw affecting Cisco Secure Firewall Management Center (FMC) software... It allows an unauthenticated remote attacker to execute arbitrary Java code with root privileges on affected FMC devices... Interlock had already begun exploiting this flaw as early as January 26, 2026.
The Java variant adds two features... The UpdateThread creates a self-deleting scheduled task... Like the Java variant, the PE uses self-deleting scheduled tasks... A daily scheduled task runs the ransomware at 20:00 as SYSTEM.
The Java variant adds two features... The UpdateThread creates a self-deleting scheduled task... Like the Java variant, the PE uses self-deleting scheduled tasks... A daily scheduled task runs the ransomware at 20:00 as SYSTEM.
“Interlock ransomware deploys “Hotta Killer” exploiting ... driver zero-day (CVE-2025-61155) to disable EDR/AV...”
The Windows variant imports wevtapi.dll and calls EvtClearLog to wipe Windows event logs. This is the only variant in the toolkit that clears event logs.
DELETE 0x0c fs.rmSync(__filename)... If the counter passes 40, the implant deletes itself... self-deleting scheduled task... --delete (self-delete after encryption)
A PowerShell-based reconnaissance script systematically collects detailed system and network information... and active connections.
One variant, written in JavaScript... establish[es] encrypted communication with command-and-control servers via WebSockets.
Interlock employs a Bash script that converts compromised Linux servers into HTTP reverse proxies. These proxies forward traffic to attacker-controlled systems while erasing logs every five minutes.
This triggered the next phase of the attack, where Interlock issued commands to download and execute a malicious Linux binary.
Such activity is significant as it often indicates ransomware behavior, where files are encrypted and the originals are deleted.
70 indicators attributed across vendor reports, sandbox runs, and researcher write-ups. Full values are available in Mallory.
IPs, domains, and DNS infrastructure linked to this family.
File hashes (MD5, SHA-1, SHA-256) from samples and reports.
Other indicator types observed in public reporting.
56 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Ransomware family/group mentioned as responsible for several attacks against the education sector in the period discussed.
Ransomware that combines data theft with encryption and extortion. In this intrusion it used ClickFix-based initial access, abused legitimate memory forensics tools to extract NTLM/LM hashes and account data, moved laterally to a domain controller, tampered with security tools, stole data, and ultimately deployed a ransomware payload.
A newer ransomware strain in 2025 with cross-platform targeting including Windows, Linux, and VMware ESXi environments.
A ransomware group/family highlighted as using multiple attack paths for initial access, including ClickFix-style social engineering that tricks users into executing commands which run malware, harvest credentials, and enable lateral movement.
Match every observed IP, domain, and hash against your live telemetry.
Named campaigns wielding this family, with evidence pinned to each claim.
CVEs this family uses for access and lateral movement.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Every documented technique, ranked by evidence weight.
Reddit, Mastodon, and CTI community discussion around this family.