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Gentlemen Ransomware Exploits Vulnerable Driver to Disable Security Tools

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📰 1 unique sources, 1 articles

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The Gentlemen ransomware gang uses a vulnerable driver to evade detection and disable security products in enterprise environments. The group employs a bring-your-own-vulnerable-driver (BYOVD) attack, leveraging the ThrottleStop.sys driver to terminate antivirus and EDR processes. The ransomware has been observed since this summer and demonstrates advanced capabilities, including tailored bypasses for specific security vendors. The vulnerability (CVE-2025-7771) was discovered by Kaspersky researchers during a ransomware incident in Brazil. The Gentlemen ransomware uses ThrottleBlood.sys, a renamed version of the legitimate ThrottleStop.sys driver, to exploit the vulnerability and gain kernel-level access. The ransomware also employs All.exe and Allpatch2.exe, which are AV killers designed to terminate security software and disable protective services. The group has shifted from generic attacks to more customized and targeted approaches, adapting their tactics based on the security defenses of their targets. They use PowerRun.exe for privilege escalation and to bypass security products.

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  1. 11.09.2025 23:42 📰 1 articles · ⏱ 5d ago

    Gentlemen Ransomware Exploits Vulnerable Driver to Disable Security Tools

    The Gentlemen ransomware gang uses a BYOVD attack to disable security products in enterprise environments. The group employs the ThrottleStop.sys driver, renamed as ThrottleBlood.sys, to exploit the vulnerability (CVE-2025-7771) and gain kernel-level access. The ransomware uses All.exe and Allpatch2.exe to terminate security software and disable protective services. The group has shifted from generic attacks to more customized and targeted approaches, adapting their tactics based on the security defenses of their targets.

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