Cybersecurity researchers at Microsoft have identified a critical vulnerability in the Windows Common Log File System that is being actively exploited by the RansomEXX ransomware gang. This high-severity zero-day flaw, labeled CVE-2025-29824, potentially allows local attackers with minimal privileges to escalate their access rights to SYSTEM level without requiring any user interaction. Such vulnerabilities are rare and critical, as they can provide attackers with full control of affected systems.
Details of the Vulnerability
The root of this breach lies in a use-after-free weakness, a common yet dangerous issue in software engineering that occurs when a program attempts to access memory after it has already been freed. In this case, the flaw allows attackers to manipulate the system for unauthorized access, further enabling the execution of arbitrary code at a privileged level.
As mitigation efforts are underway, Microsoft has released security updates to patch the vulnerability in affected Windows versions. However, the rollout for Windows 10 systems has faced delays, leaving these users temporarily exposed to this severe threat.
Scope of Impact
This breach predominantly targets sectors such as IT, real estate, financial services, and retail industries, highlighting the opportunistic nature of cybercriminals targeting sectors with valuable data assets. The attack involved the deployment of PipeMagic backdoor malware, a sophisticated tool used to gain initial entry. Following infiltration, the attackers deployed exploits and ransomware payloads, effectively encrypting files and subsequently delivering ransom demands to the victims.
Encouragingly, organizations running Windows 11, version 24H2 are reported to be immune to this flaw, providing a temporary sigh of relief for some users. Nevertheless, the risk remains high for those who have not installed the latest patches or are using versions with pending updates.
Security experts emphasize the critical importance of promptly applying security updates and maintaining robust cybersecurity protocols to safeguard against such pervasive threats. As the frequency of zero-day exploits continues to rise, organizations are urged to prioritize cybersecurity to protect their infrastructure and sensitive data from sophisticated attack vectors like the RansomEXX.
In light of these developments, ongoing monitoring and quick reaction to new attacks are crucial for organizations to mitigate the impact of these threats effectively. Microsoft continues to collaborate with security experts across the globe to stay ahead of these evolving threats, striving to secure their systems for all users worldwide.