The Gentlemen Ransomware Claims 478 Victims, Can Spread Like a Worm
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2024-55591 | Unauthenticated Super-Admin Bypass in Fortinet FortiOS and FortiProxy CVE-2024-55591 is an authentication bypass (CWE-288) in the Node.js websocket module of Fortinet FortiOS and FortiProxy that lets a remote, unauthenticated attacker gain super-admin privileges via crafted websocket requests. It affects FortiOS 7.0.0 through 7.0.16 and FortiProxy 7.0.0 through 7.0.19 and 7.2.0 through 7.2.12, and is trivially triggerable from the network with no user interaction given network access to the management/websocket interface. Successful exploitation gives full super-admin control of the appliance, which attackers can use to pivot, create persistent access, and deploy ransomware. Any organization running the affected FortiOS or FortiProxy versions, especially with admin interfaces reachable from the internet, is affected. Exploitation is confirmed in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2025-01-14, and multiple ransomware crews (reported as Gunra, SuperBlack, and Mora_001) are actively exploiting it. Do: Upgrade all affected systems beyond the vulnerable ranges — FortiOS later than 7.0.16 and FortiProxy later than 7.0.19 / 7.2.12 — following Fortinet's advisory, or apply the vendor's mitigations where upgrades are not possible (per CISA KEV instructions). Restrict access to the admin/websocket interface from the internet, and hunt for unauthorized super-admin accounts and suspicious websocket connections, since ransomware operators are actively exploiting this flaw. Verify device versions and audit logs for signs of compromise before and after patching. | 9.8 | 98% | KEV ransomware |
| large≈48,000+ internet-exposed Fortinet devices per public scans, out of an installed base in the hundreds of thousands | |
| CVE-2025-32433 | Unauthenticated RCE in Erlang/OTP SSH Server CVE-2025-32433 is a missing-authentication flaw (CWE-306) in the SSH server shipped with Erlang/OTP, the runtime and libraries of the Erlang programming language. An unauthenticated attacker can send specially crafted SSH protocol messages to a vulnerable Erlang/OTP SSH daemon before authentication and trigger remote code execution. Successful exploitation yields arbitrary command execution on the host with the privileges of the SSH service, and the CVSS scope change (S:C) indicates compromise can cascade to resources beyond the vulnerable component. Affected are any systems exposing the Erlang/OTP SSH server, including standalone Erlang deployments, Debian-packaged Erlang, and Cisco products that embed Erlang/OTP (e.g., Network Services Orchestrator, ConfD Basic, Ultra Packet Core). Exploitation is confirmed in the wild: a public proof-of-concept exists, the bug was added to CISA KEV on 2025-06-09, and researchers report a surge in exploitation attempts, with roughly 70% of observed attacks targeting OT firewalls. Do: Upgrade Erlang/OTP to OTP-27.3.3, OTP-26.2.5.11, or OTP-25.3.2.20 depending on the release branch, and apply the corresponding updates from Cisco and Debian for embedded/packaged Erlang. Until patched, disable the Erlang SSH daemon or restrict access to it with firewall rules, prioritizing internet-exposed hosts and OT firewall devices where ~70% of observed attacks have landed. Federal agencies must apply mitigations per vendor instructions under the KEV/BOD 22-01 requirements. | 10.0 | 99% | KEV PoC |
| largetens of thousands of internet-exposed Erlang/OTP SSH servers, plus an unknown additional embedded installed base in telecom/network equipment (Cisco NSO,… | |
| CVE-2025-33073 | Improper Access Control Privilege Escalation in Microsoft Windows SMB Client CVE-2025-33073 is an improper access control flaw (CWE-284) in the Windows SMB client that allows an authorized, low-privileged attacker to elevate privileges over the network (CVSS 3.1: 8.8). The attack is network-based with low attack complexity and no user interaction: the attacker must get a vulnerable Windows machine's SMB client to connect to their crafted SMB server, and crafted server responses during the client's authentication flow cause the client to grant the attacker elevated (reportedly SYSTEM-level) access. An attacker gains local privilege elevation on the connecting Windows client, which can be used for full host compromise and lateral movement. Affected systems include essentially all currently supported Windows desktop and server branches in the data: Windows 10 (1507, 1607, 1809, 21H2, 22H2), Windows 11 (22H2, 23H2, 24H2), and Windows Server 2008, 2012, 2016 and 2019. The flaw is actively exploited in the wild — CISA added it to the KEV catalog on 2025-10-20 (ransomware linkage unknown), and EPSS places it at an 80.5% probability of exploitation within 30 days (100th percentile). Do: Apply Microsoft's June 2025 (or later) cumulative security updates that address CVE-2025-33073 on all listed Windows 10, Windows 11, and Windows Server systems, prioritizing domain-critical, internet-reachable, and server assets given active exploitation. If immediate patching is not possible, restrict SMB client access to trusted servers and follow Microsoft guidance on hardening NTLM authentication; note that federal agencies must meet CISA KEV/BOD 22-01 remediation timelines following the 2025-10-20 KEV listing. Verify the update actually landed on each host (checking that CVE-2025-33073 is listed as addressed) and hunt for connections to untrusted SMB servers from Windows clients. | 8.8 | 83% | KEV |
| masshundreds of millions of Windows endpoints and servers (SMB client is present and reachable by default across the listed Windows 10/11 and Windows Server… |
Indicators of compromiseauto-extracted · verify before use · export allAll →
| Type | Indicator | Context |
|---|---|---|
| domain | hunt.io | ipeline," Check Point said . That's not all. In March 2026, Hunt.io said it discovered an open directory hosted at "176.120.22[ |
Full article1,239 words · extracted from thehackernews.com · click to collapse
A new analysis of The Gentlemen operation has revealed that the financially motivated threat group initially operated as an affiliate responsible for conducting double extortion attacks, while leveraging resources from various ransomware-as-a-service (RaaS) schemes like LockBit (aka Tenacious Mantis), Qilin (aka Pestilent Mantis), and Medusa (aka Venomous Mantis).
According to a detailed report published by PRODAFT, the group, which it tracks as Phantom Mantis, is led by a Russian-speaking cybercriminal it calls LARVA-368, who goes by the online aliases hastalamuerte, ArmCorp, zeta88, nobody0, and santamuerte. The Gentlemen is known to be active since March 2025, claiming a total of 478 victims to date, per data from Ransomware.Live.
"In July 2025, Phantom Mantis transitioned into The Gentlemen, an independent partnership program no longer dependent on other RaaS groups," the Swiss cybersecurity company said. "Additionally, LARVA-368 relies heavily on artificial intelligence for the development and maintenance of ransomware and tools, as well as for assistance with post-exploitation procedures."
As for LARVA-368, the threat actor is assessed to have been a member of the Embargo (aka Primeval Mantis) ransomware group before launching their own operation under the name ArmCorp. It was subsequently rebranded to The Gentlemen four months later.
The individual's identity has since been outed by cybersecurity journalist Brian Krebs as a 36-year-old Alexander Andreevich Yapaev (Япаев Алексанр Андреевич) from the Russian city of Izhevsk. PRODAFT told The Hacker News that its findings match the same persona with "high confidence."
As detailed by Dark Atlas in August 2025, the shift to a custom ransomware program coincided with a payment dispute between LARVA-368 and Qilin, with the threat actor accusing the RaaS operation of carrying out an exit scam and defrauding them of $48,000.
"Although Phantom Mantis was a very active affiliate group with over 20 targets registered on its affiliate panel in less than 30 days, the group's admin (LARVA-368) and LARVA-367 (aka DevMan), a former Phantom Mantis's member, claimed that Pestilent Mantis was scamming affiliates and that there was an alleged 'backdoor' within the Pestilent Mantis's affiliate panel victim chats," PRODAFT noted.
"Although we could not confirm these claims, there is a chance that LARVA-368 and LARVA-367 intentionally spread disinformation with the intent of recruiting Pestilent Mantis affiliates to Phantom Mantis by discrediting the group."
Phantom Mantis has also been observed paying for Premium accounts on underground forums to boost their visibility and fend off competition, with the group's communication and the technical support handled by a separate Russian-speaking persona named The Gentlemen Data.
Some of the other salient aspects of the extortion scheme compiled from various reports are as follows -
- In an analysis of the ransomware in late last year, LevelBlue's Cybereason team described The Gentlemen as a "highly adaptive, fast-moving ransomware operation" that combines mature ransomware techniques with RaaS features, double extortion, cross-platform lockers, and flexible propagation, and affiliate support.
- The group has emerged as one of the most active threat actors, accounting for 10% of ransomware activity in April 2026. "The Gentlemen follows an enterprise-focused chain beginning with initial access, via vulnerable internet-facing services or stolen credentials," NCC Group said. "Analysis suggests The Gentlemen can adapt and change tactics during an attack, such as manipulating GPOs, compromising privileged accounts, and using custom methods to bypass endpoint protections."
- Only about 13% of their victims are based in the U.S. The majority of the victims are concentrated in Thailand, the U.K., Brazil, Germany, and India.
- LARVA-368 uses The Gentlemen IM app accounts to support affiliates regarding encryption and any intrusion-related issue, such as providing EDR killers to bypass security solutions via the bring your own vulnerable driver (BYOVD) technique.
- Support services for both The Gentlemen and The Gentlemen Data are available via Tox, SimpleX Chat, and Ricochet Refresh open-source messaging platforms.
- Potential affiliates are required to provide the administrator at least 1GB of data exfiltrated from a victim to gain access to the affiliate panel, a tactic designed to prevent researchers and law enforcement authorities from gaining access to the infrastructure under the guise of an affiliate. The affiliate panel supports user management, configuring new targets, and downloading ransomware to a specific target.
- Phantom Mantis provides five versions of ransomware that are designed for Windows, Linux, ESXi, Windows XP+, and Logical Volume Manager (LVM).
- The group courts affiliates with an aggressive profit-sharing model: 90% for affiliates and 10% for the operator.
- Initial access is obtained via edge devices such as VPN appliances, firewalls, and other internet-facing systems, with a specific focus on platforms like Cisco and Fortinet FortiGate.
- Infection chains involve the use of red team utilities like NetExec, RelayKing, TaskHound, PrivHound, and CertiHound to perform Active Directory discovery, certificate abuse, privilege escalation, and file share discovery. A separate set of tools, such as EDRStartupHinder, gfreeze, glinker, and DumpBrowserSecrets, are used for evading security programs, while Velociraptor is employed for command-and-control (C2).
- The attacks also attempt to clear System, Application, and Security Windows Event Logs, disable Microsoft Defender, and add antivirus exclusions.
- The ransomware makes use of a hybrid cryptographic scheme: X25519 key exchange combined with XChaCha20 symmetric encryption.
- Microsoft, which is tracking the cluster under the moniker Storm-2697, said the ransomware is written in Go and obfuscated with Garble to target the Windows environment. "When enabled with the --spread argument, it turns the malware from a single-host encryptor into a self-propagating worm that attempts to deploy its encryptor to every reachable system on the network," the tech giant said. "If the --wipe argument is provided, The Gentlemen ransomware performs an additional post-encryption routine to eliminate recoverable artifacts from disk."
- According to ZeroFox, the ransomware crew likely runs a multi-channel extortion operation, combining ransomware attacks with email outreach and phone-based pressure tactics targeting victims.
- The group implements a "highly responsive development cycle," an aspect exemplified by the release of a same-day patch after a decryptor was released in April 2026.
- The average dwell time of an intrusion ranges from two to six weeks from initial access to encryption, with the group particularly focusing on organizations running VMware infrastructure.
Last month, a leak of an internal Rocket.Chat database used by the group - comprising 3,366 messages between November 2025 to late April 2026 - has shed further light on the group's inner workings, including its use of known security flaws in VMware Aria Operations, Fortinet, Cisco, and Microsoft software, while painting a picture of a criminal enterprise whose members have a clear division of roles and responsibilities.
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| Image Source: Ransom-ISAC |
"The group actively tracks and evaluates modern vulnerabilities, including CVE-2024-55591, CVE-2025-32433, and CVE-2025-33073, and combines them with technique-driven paths like backup and management-controller abuse and NTLM relay workflows, giving them a flexible exploitation pipeline," Check Point said.
That's not all. In March 2026, Hunt.io said it discovered an open directory hosted at "176.120.22[.]127:80" on the Russian bulletproof hosting provider Proton66 that exposed 126 files containing a complete ransomware operator toolkit attributed to a The Gentlemen RaaS affiliate.
This included tools for reconnaissance, privilege escalation, defense evasion, credential theft, lateral movement, persistence, and pre-encryption preparation, essentially spanning all phases of the intrusion lifecycle.
"LARVA-368 is a threat actor specializing in extortion-related activities and has been active since at least 2020," PRODAFT said. "The expertise acquired through previous collaborations with various RaaS groups provided the technical foundation necessary to establish The Gentlemen RaaS."
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Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2026/06/the-gentlemen-ransomware-claims-478.html
