Play Ransomware Gang Leverages Zero-Day to Deploy Malware

The Exploit Unveiled

Recently, the Play ransomware gang has made headlines by exploiting a crucial vulnerability in the Windows operating system. This flaw, known as CVE-2025-29824, affects the Windows Common Log File System driver and has been classified with a CVSS score of 7.8, indicating its severity. By successfully leveraging this zero-day exploit, attackers can gain SYSTEM privileges, allowing them to deploy various forms of malware onto compromised systems.

Understanding the Vulnerability

The CVE-2025-29824 vulnerability represents a Use After Free condition within the Common Log File System Driver. This type of vulnerability can allow an authorized attacker to escalate privileges locally. Exploiting this flaw enables adversaries to gain high-level access to the system, giving them virtually unrestricted capabilities.

The urgency of resolving this vulnerability was underscored by the U.S. Cybersecurity and Infrastructure Security Agency (CISA), which added it to its Known Exploited Vulnerabilities (KEV) catalog back in April 2025. Following these alerts, Microsoft patched the issue in its April Patch Tuesday security updates, but not before it had already been exploited in real-world attacks.

Real-World Impact

The ramifications of this flaw became evident when Microsoft confirmed that it had been exploited in multiple, albeit limited, attacks. Notably, organizations across various sectors, including IT and real estate in the United States and retail in Saudi Arabia, were targeted.

One of the most significant findings originates from Symantec’s Threat Hunter Team, which reported that the Play ransomware gang used this zero-day exploit during their attempted attack on a U.S. organization. While no ransomware was deployed in this particular intrusion, attackers did utilize a tool known as Grixba, an infostealer associated with the Balloonfly cybercrime group—a key player behind the Play ransomware operation.

Attack Vector and Methodology

Investigations revealed how the attackers devised their assault. They exploited a public-facing Cisco ASA firewall as the initial infection vector. From there, they gained access to a Windows system and proceeded to deploy tools, including Grixba and the CVE-2025-29824 exploit itself.

Once inside the system, attackers used PowerShell to extract information from Active Directory. By taking advantage of the CLFS driver vulnerability, they escalated their privileges further. The group executed various malicious DLLs and scripts aimed at stealing credentials and even established additional admin accounts to facilitate further action. In a strategic move to evade detection, they also conducted operations to cover their tracks. The exploit manipulated race conditions in driver memory handling, granting them kernel access and maintaining persistence through scheduled tasks.

Broader Context and Threat Landscape

The CVE-2025-29824 exploit marked a notable moment in the ongoing battle against ransomware and the broader cyber threat landscape. While it’s not unprecedented for ransomware actors to utilize zero-day vulnerabilities, such occurrences remain relatively rare.

Before being patched by Microsoft, various threat actors had already leveraged this flaw, with security reports linking it to PipeMagic malware and Storm-2460 operations. Symantec also noted different non-fileless uses of the exploit, indicating a multifaceted approach by the attackers.

Final Thoughts

The dynamics of modern cybercrime are evolving, with ransomware groups like Play utilizing increasingly sophisticated methods to breach systems. The emergence of zero-day exploits like CVE-2025-29824 not only underscores the importance of timely patches and updates but also highlights the constant cat-and-mouse game between cybersecurity professionals and malicious actors.

As organizations and cybersecurity teams brace for the complexities of these evolving threats, staying informed about vulnerabilities and arming themselves with the right tools and knowledge is essential in combating the nefarious actions of ransomware gangs.

For ongoing updates and insights, you can follow cybersecurity expert Pierluigi Paganini on social media platforms like Twitter and Facebook, as well as on Mastodon.