CVE-2021-26895

CVE-2021-26895

Critical · published March 11, 2021

CVSS v3.1
9.8
EPSS
8%
Percentile
94.6
In the wild
Unconfirmed
What it is

🚨 An unpatched Windows DNS Server is a ticking time bomb! This critical vulnerability allows attackers to execute remote code and take control without breaking a sweat. 🔥 Think of it like a restaurant with a menu that lets anyone order off it without verification—an open invitation for anyone to serve themselves from the kitchen! If exploited, an attacker could gain full control of the DNS server, allowing them to manipulate traffic, serve malicious payloads, or even exfiltrate sensitive data. This could lead to devastating consequences for your network and the users relying on it—think of all the data and operations that could be compromised!

Put simply

Think of it like a restaurant with a menu that lets anyone order off it without verification—an open invitation for anyone to serve themselves from the kitchen! This vulnerability in Windows DNS Server allows remote code execution due to improper handling of requests, enabling an attacker to send specially crafted requests that the server naively processes, granting them control of the server.

What to do

If exploited, an attacker could gain full control of the DNS server, allowing them to manipulate traffic, serve malicious payloads, or even exfiltrate sensitive data. This could lead to devastating consequences for your network and the users relying on it—think of all the data and operations that could be compromised! To protect your systems, patch the Windows DNS Server immediately to version 2012 or later. Additionally, consider implementing network segmentation to limit exposure and monitor DNS logs for any suspicious activity. Don't wait—act now! You've got this! By following these steps, you can secure your environment and keep the bad actors at bay. 🛡️

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.07755 · 94.6th percentile
Published
2021-03-11T21:15Z
Affected products (10)
ProductVersionsFixed in
microsoft/windows_server_2008all versions—
microsoft/windows_server_2008all versions—
microsoft/windows_server_2008all versions—
microsoft/windows_server_2012all versions—
microsoft/windows_server_2012all versions—
microsoft/windows_server_2016all versions—
microsoft/windows_server_2016all versions—
microsoft/windows_server_2016all versions—
microsoft/windows_server_2016all versions—
microsoft/windows_server_2019all versions—
References (2)
EPSS history
Timeline
  • 11 MAR 15:43Z
    Windows DNS Server Remote Code Execution Vulnerability
    cvelistv5