inetpub Archives

Winsage

June 9, 2025

If you deleted that mysterious Windows file Microsoft told you not to, there’s a new script to restore it

The 'inetpub' folder, which appears on system drives (C:) after the April 2025 security update for Windows 10 and 11, is essential for protecting users against the security vulnerability CVE-2025-21204. This vulnerability involves improper link resolution before file access and can allow an authorized attacker to escalate privileges. Although the folder may seem empty and Internet Information Services (IIS) might not be in use, its deletion can compromise the effectiveness of the security patch, exposing systems to vulnerabilities. Microsoft recommends using a PowerShell script to restore the folder if deleted, rather than recreating it through IIS, which may add unwanted system folders.

Winsage

June 9, 2025

Microsoft: Remedy for security vulnerability due to deleted “inetpub” folder

A recent Microsoft security update has created a new folder named "inetpub" on Windows systems, which is essential for system security. If users delete this folder, it can lead to significant vulnerabilities. Microsoft has released a Powershell script, Set-InetpubFolderAcl.ps1, to restore the "inetpub" folder and set the correct permissions. Systems that installed the April security update (KB5055528) must take immediate action if the "inetpub" directory is missing. The script also updates access rights for the "DeviceHealthAttestation" directory, if it exists. Administrative rights are required to run the script. This issue was highlighted by IT security researcher Kevin Beaumont, who noted that deleting the "inetpub" folder could disrupt the installation of future security updates.

Winsage

June 6, 2025

Microsoft shares script to restore inetpub folder you shouldn’t delete

Microsoft has released a PowerShell script to help restore the C:Inetpub folder, which is crucial for addressing a high-severity privilege escalation vulnerability associated with Windows Process Activation. The folder's unexpected appearance after the April 2025 Windows security updates led some users to delete it, inadvertently exposing their systems to vulnerabilities. Microsoft emphasizes that the folder should not be deleted, as it is integral to the security framework, regardless of whether Internet Information Services (IIS) is active. The script allows administrators to recreate the folder with the correct permissions and access control settings.

Winsage

June 6, 2025

Microsoft Issues Critical Windows Update—Do Not Delete This

Users may face a significant vulnerability related to a Windows update from April 2025, particularly concerning the "inetpub" folder, which is essential for the security of Windows 11 systems. Microsoft clarified that this folder, linked to Internet Information Services (IIS) and necessary for hosting capabilities, should not be deleted. If users have removed the folder, they must restore it to address the security patch for CVE-2025-21204, as its absence can lead to risks such as privilege escalation and unauthorized access. Microsoft has provided a PowerShell script to restore the folder without enabling IIS, and users are advised to follow specific commands to execute the fix. However, many users may not take action, leaving their systems vulnerable.

Winsage

June 6, 2025

Your Windows PC might be at risk if you deleted the “inetpub” folder, but there’s a fix

Windows users have encountered a new "inetpub" folder on their primary drive after the April 2025 Patch Tuesday update. This folder is empty and occupies no storage space, but many users have deleted it out of concern. Microsoft has stated that the folder is part of a security patch for vulnerability CVE-2025-21204 and should not be removed, as it is linked to Internet Information Services (IIS). Users can restore the folder using a PowerShell script if they have deleted it. The folder addresses a security flaw related to improper link resolution that could allow local attackers to manipulate files. Instructions for restoring the folder include running PowerShell as Administrator, allowing signed scripts, downloading a specific script, and applying the fix.

Winsage

May 10, 2025

Microsoft’s New Windows Update — 1 Billion Users Warned: Do Not Delete

Windows users are facing security challenges, including zero-day vulnerabilities and hackers bypassing Windows Defender. Microsoft has removed VPN provisions for Windows Defender and discontinued security support for Windows 10, but users can upgrade to Windows 11 for free. Following the April 8 Patch Tuesday updates, a new folder named "inetpub" appeared on user devices, which Microsoft has warned users not to delete, as it is essential for security protections. This folder is generated after installing updates and is traditionally associated with the Internet Information Services (IIS) web server platform, regardless of whether IIS is installed. If users have deleted the inetpub folder, it can be restored by enabling IIS through the Windows Control Panel.

Winsage

April 30, 2025

A mysterious new Windows 11 folder appeared – and now there’s a new exploit

Windows 11 users encountered the "inetpub" folder after the April 2023 update (KB5055523), which is a crucial component for addressing the security vulnerability CVE-2025-21204. Microsoft stated that the folder should not be removed, as it helps manage Windows Update security vulnerabilities by preventing unauthorized control through symbolic links. However, cybersecurity expert Kevin Beaumont revealed that the same patch introduced a new vulnerability that could allow remote exploitation, prompting Microsoft to acknowledge this issue with a "Moderate" status and indicate that a fix is forthcoming. Users are advised to keep their systems updated and not delete the "inetpub" folder. If the folder is deleted, it can be restored by enabling Internet Information Services in the Control Panel.

Winsage

April 27, 2025

New Security Warning After 1 Billion Windows Users Told Do Not Delete

Microsoft's recent security update for Windows has raised concerns among users due to the introduction of a new vulnerability. The update, intended to address the CVE-2025-21204 vulnerability, inadvertently created a folder named inetpub, which Microsoft claims is essential for user protection. Security researcher Kevin Beaumont has warned that this update has introduced a denial of service vulnerability that allows non-admin users to halt future Windows security updates. Microsoft has classified the issue as moderate in severity and suggested that deleting the inetpub symlink and retrying the update may resolve the problem. The report has been forwarded to the Windows security team for potential further action.

Winsage

April 25, 2025

Windows “inetpub” security fix can be abused to block future updates

A recent Microsoft security update has created a new 'inetpub' folder in the root of the system drive, linked to a fix for a Windows Process Activation elevation of privilege vulnerability (CVE-2025-21204). This folder has appeared on systems without Internet Information Services (IIS) installed. Microsoft advises users not to delete the folder, as it enhances system protection. However, cybersecurity expert Kevin Beaumont has shown that the 'inetpub' folder can be manipulated by non-administrative users to create a junction that redirects to a Windows file, potentially obstructing future Windows updates and resulting in a 0x800F081F error code. Microsoft has classified this issue as "Medium" severity and has closed the case, indicating it may be addressed in future updates.

Winsage

April 25, 2025

Microsoft’s Patch for Symlink Vulnerability Introduces New Windows Denial-of-Service Flaw

In early April 2025, Microsoft addressed a security vulnerability (CVE-2025-21204) related to symbolic links in the Windows servicing stack, specifically affecting the c:inetpub directory used by Internet Information Services (IIS). The updates created the c:inetpub folder with appropriate permissions to mitigate risks. However, this fix introduced a new denial-of-service (DoS) vulnerability, allowing non-administrative users to create junction points on the c: drive, disrupting the Windows Update mechanism. A command such as "mklink /j c:inetpub c:windowssystem32notepad.exe" could be used to exploit this flaw, preventing systems from receiving future security patches. As of April 25, Microsoft had not released a patch or acknowledged the issue, leaving systems vulnerable and emphasizing the need for monitoring user permissions and manually removing suspicious symlinks.