September 27, 2024 at 03:44PM
Researchers have identified a medium-severity vulnerability in Windows, labeled as CVE-2024-6769, which could enable an authenticated attacker to gain full system privileges. Fortra’s proof-of-concept exploit showcases the capability to shut down the system and manipulate critical files, despite Microsoft’s stance that it falls under acceptable security boundaries. The vulnerability allows an attacker to bypass user integrity levels and escalate privileges without triggering User Account Control (UAC). Despite Microsoft’s perspective, Fortra emphasizes the importance for businesses to be vigilant against the risk of UAC bypass.
From the meeting notes, it is evident that researchers have identified a vulnerability in Windows known as CVE-2024-6769. This security issue presents a combination of user access control (UAC) bypass and privilege escalation, allowing an attacker to gain full system privileges. Fortra has given the vulnerability a medium severity score of 6.7 out of 10 on the Common Vulnerability Scoring System (CVSS) scale. Microsoft, however, does not consider this vulnerability as it falls under their concept of acceptability, stating that “non-robust” security boundaries are permitted.
The vulnerability revolves around the concept of Mandatory Integrity Control (MIC) introduced in Windows Vista, which assigns integrity levels to users, processes, and resources. The exploitation involves jumping across the security boundary imposed on the medium integrity level to obtain full administrative privileges without triggering UAC.
To exploit this vulnerability, an attacker first needs a foothold in the targeted system with medium integrity-level privileges. They then proceed with steps such as remapping the system’s root drive, placing a specially crafted DLL, and poisoning the activation context cache to gain full administrative privileges.
Despite Fortra’s concerns and demonstration of the potential risk, Microsoft refuses to acknowledge the issue as a vulnerability. They argue that the trust boundary between admin user and system is acceptable, considering that admin users can perform the same system-level actions subject to UAC approval.
While there exists a philosophical difference, Fortra emphasizes the importance for businesses to be aware of the risk and take precautions, especially in allowing lower-integrity admins to escalate their privileges. At the end of an exploit, an attacker could have full control over critical system files, upload malware, establish persistence, and more.
In conclusion, even though Microsoft does not consider CVE-2024-6769 a vulnerability, it’s essential for Windows shops to remain vigilant and take necessary measures to mitigate the potential risk associated with this exploit.