CVE-2021-26867

CVE-2021-26867

Critical · published March 11, 2021

CVSS v3.1
9.9
EPSS
3%
Percentile
86.7
In the wild
Unconfirmed
What it is

🚨 A critical flaw in Hyper-V could allow attackers to execute arbitrary code remotely! 💥 Think of Hyper-V like a high-tech hotel where guests can access different rooms (virtual machines) without a proper keycard. If a hacker finds a way in, they could wander through the corridors and take control of anything they like — potentially wreaking havoc! An attacker could exploit this vulnerability to gain complete control over the Hyper-V server, allowing them to execute malicious code, steal sensitive information, or disrupt operations entirely. This could lead to an organization facing devastating data breaches or system failures—yikes! 🔥

Put simply

Think of Hyper-V like a high-tech hotel where guests can access different rooms (virtual machines) without a proper keycard. If a hacker finds a way in, they could wander through the corridors and take control of anything they like — potentially wreaking havoc! This vulnerability allows remote code execution by sending specially crafted requests to the Hyper-V service. If successful, it could allow attackers to bypass security controls entirely and gain unauthorized access to virtual machines.

What to do

An attacker could exploit this vulnerability to gain complete control over the Hyper-V server, allowing them to execute malicious code, steal sensitive information, or disrupt operations entirely. This could lead to an organization facing devastating data breaches or system failures—yikes! 🔥 To protect your systems, patch immediately to the latest Windows updates that address this CVE. Ensure that your firewall configurations are tight, and consider implementing additional layers of monitoring around your Hyper-V environments. You've got this! With prompt action, you can secure your Hyper-V setup and keep the bad guys at bay! 🛡️

The record
Technical detail
CVSS v3.1
9.9 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.02866 · 86.7th percentile
Published
2021-03-11T21:15Z
Affected products (6)
ProductVersionsFixed in
microsoft/windows_10all versions—
microsoft/windows_10all versions—
microsoft/windows_10all versions—
microsoft/windows_server_2016all versions—
microsoft/windows_server_2016all versions—
microsoft/windows_server_2016all versions—
References (2)
EPSS history
Timeline
  • 11 MAR 15:38Z
    Windows Hyper-V Remote Code Execution Vulnerability
    cvelistv5