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UNC5174 Exploits VMware Zero-Day Privilege Escalation Since October 2024

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A China-linked threat actor, UNC5174, has been exploiting a zero-day privilege escalation vulnerability in VMware products since mid-October 2024. The flaw, CVE-2025-41244, affects multiple VMware products and allows local attackers to escalate privileges to root on affected virtual machines. The vulnerability was discovered in May 2025 and patched in VMware Tools 12.4.9 and later versions. The flaw is rooted in the get_version() function, which can be exploited by placing a malicious binary in a writable directory. UNC5174 has been observed using this method to gain elevated access and execute code on compromised systems. The exact payload and nature of the attacks remain unclear. Broadcom has confirmed the patch for the vulnerability in VMware Aria Operations and VMware Tools. NVISO released a proof-of-concept exploit demonstrating privilege escalation on vulnerable VMware software. UNC5174 has been linked to previous attacks on U.S. defense contractors, UK government entities, and Asian institutions, exploiting vulnerabilities such as F5 BIG-IP CVE-2023-46747 and ConnectWise ScreenConnect flaw.

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  1. 30.09.2025 13:57 2 articles · 6h ago

    UNC5174 Exploits VMware Zero-Day Privilege Escalation Since October 2024

    Broadcom has confirmed the patch for the vulnerability in VMware Aria Operations and VMware Tools. NVISO released a proof-of-concept exploit demonstrating privilege escalation on vulnerable VMware software. UNC5174 has been linked to previous attacks on U.S. defense contractors, UK government entities, and Asian institutions, exploiting vulnerabilities such as F5 BIG-IP CVE-2023-46747 and ConnectWise ScreenConnect flaw.

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