Ethical Hacking News
Zero-Day Ransomware Exploits: A Growing Threat to U.S. Organizations
A recent attack on an unnamed organization in the United States has highlighted the growing concern of threat actors using zero-days to infiltrate targets. The exploitation of CVE-2025-29824, a privilege escalation flaw in the Common Log File System (CLFS) driver, was used as a zero-day by Play ransomware family in their attack. This article explores the use of zero-day ransomware exploits and provides insights into the tactics used by threat actors to disable security measures and gain access to sensitive information.
Zero-day ransomware exploits are a growing concern for organizations, with recent attacks highlighting the difficulty in detecting and responding to these threats. The exploitation of CVE-2025-29824, a privilege escalation flaw in the CLFS driver, was used as a zero-day by Play ransomware family in their attack. Threat actors are leveraging public-facing Cisco Adaptive Security Appliance (ASA) as entry points, and using bespoke information stealers like Grixba to gather information about target networks. Ransomware attackers are using exploits for zero-day vulnerabilities to move laterally within networks, often creating backdoors like the DLL injected into winlogon.exe. The use of zero-day exploits is a significant concern due to their difficulty in detection and response, highlighting the importance of staying up-to-date with security patches.
The world of cybersecurity is constantly evolving, and one of the most significant threats that organizations face today is the rise of zero-day ransomware exploits. A recent attack on an unnamed organization in the United States has highlighted the growing concern of threat actors using zero-days to infiltrate targets. The exploitation of CVE-2025-29824, a privilege escalation flaw in the Common Log File System (CLFS) driver, was used as a zero-day by Play ransomware family in their attack.
Symantec Threat Hunter Team, part of Broadcom, has observed that the threat actors likely leveraged a public-facing Cisco Adaptive Security Appliance (ASA) as an entry point, taking advantage of an as-yet-undetermined method to move to another Windows machine on the target network. The attackers also employed Grixba, a bespoke information stealer previously attributed to Play ransomware family, along with an exploit for CVE-2025-29824 that's dropped in the Music folder, giving it names that masquerade as Palo Alto Networks software.
The attackers have also been observed running commands to gather information about all the available machines in the victims' Active Directory and save the results to a CSV file. Two files were created in the path C:\ProgramData\SkyPDF during the execution of the exploit, with one being a Common Log File System base log file and the other being a DLL that is injected into the winlogon.exe process.
The DLL has the ability to drop two additional batch files, "servtask.bat" and "cmdpostfix.bat". The first batch file, "servtask.bat", is used to escalate privileges, dump the SAM, SYSTEM, and SECURITY Registry hives, create a new user named "LocalSvc," and it to the Administrator group. On the other hand, the second batch file, "cmdpostfix.bat," is used to clean up traces of exploitation.
Symantec said that no ransomware payload was deployed in the intrusion, and that exploits for CVE-2025-29824 may have been available to multiple threat actors before it was fixed by Microsoft. This finding points to a trend of ransomware actors using zero-days to infiltrate targets.
The use of zero-day exploits is a significant concern because they can be extremely difficult to detect and respond to, especially if the organization does not have adequate security measures in place. The fact that exploit for CVE-2025-29824 was used as a zero-day highlights the importance of staying up-to-date with the latest security patches.
In addition to the Play ransomware family, another ransomware group called Crytox has employed HRSword as part of their attack chain to turn off endpoint security protections. This is a growing trend where threat actors are using a variety of techniques to disable security measures and gain access to sensitive information.
Furthermore, new ransomware trends have emerged in recent months, with more than 78% of human-operated cyberattacks successfully breaching domain controllers. In over 35% of cases, the primary spreader device is the system responsible for distributing ransomware at scale, which highlights its crucial role in enabling widespread encryption and operational disruption.
The development of RansomHub, a RaaS scheme that abruptly ceased operations at the end of March 2025, has also coincided with the launch of a ransomware cartel by DragonForce. This raises concerns about the rise of organized crime groups involved in ransomware attacks.
In conclusion, the use of zero-day ransomware exploits is becoming increasingly common, and it is essential for organizations to take proactive measures to prevent such attacks. Staying up-to-date with security patches, implementing robust security measures, and conducting regular threat intelligence can help reduce the risk of such attacks.
The recent attack on the U.S. organization serves as a wake-up call for businesses to prioritize their cybersecurity posture. By understanding the tactics used by ransomware attackers and staying ahead of emerging threats, organizations can minimize their exposure to zero-day exploits and protect themselves from potential breaches.
Related Information:
https://www.ethicalhackingnews.com/articles/Zero-Day-Ransomware-Exploits-A-Growing-Threat-to-US-Organizations-ehn.shtml
https://thehackernews.com/2025/05/play-ransomware-exploited-windows-cve.html
https://nvd.nist.gov/vuln/detail/CVE-2025-29824
https://www.cvedetails.com/cve/CVE-2025-29824/
https://www.resecurity.com/blog/article/dragonforce-ransomware-reverse-engineering-report
https://blog.checkpoint.com/security/dragonforce-ransomware-redefining-hybrid-extortion-in-2025/
https://www.zscaler.com/blogs/security-research/technical-analysis-crytox-ransomware
https://securityboulevard.com/2022/09/technical-analysis-of-crytox-ransomware/
Published: Wed May 7 06:36:52 2025 by llama3.2 3B Q4_K_M
