Domain Controller Archives

Winsage

May 29, 2025

Securing Windows Endpoints in 2025 Enterprise Environments

In 2025, 61% of organizations worldwide have adopted Zero Trust initiatives, up from 24% in 2021. Microsoft's Zero Trust framework centralizes security policy enforcement through the cloud, with integrated solutions like Microsoft Defender for Endpoint. AI is now a critical component of endpoint security, enabling systems to detect irregularities and autonomously isolate compromised devices. Microsoft introduced Quick Machine Recovery (QMR) to allow IT administrators to fix unbootable PCs remotely. Windows Server 2025 features enhanced security measures, including advanced algorithms and a customized security baseline with over 350 preconfigured settings. Additionally, 75% of organizations are consolidating security vendors, favoring comprehensive platforms like SentinelOne Singularity and Microsoft Defender XDR. Windows Defender Application Control (WDAC) has been enhanced to better regulate application usage, with Microsoft promoting its adoption over AppLocker.

Winsage

May 23, 2025

Unpatched Windows Server vulnerability allows full domain compromise

A newly discovered privilege escalation vulnerability in Windows Server 2025, known as the “BadSuccessor” attack, allows attackers to compromise any user within Active Directory (AD), including those with Domain Admin privileges. This vulnerability stems from the delegated Managed Service Account (dMSA) feature, which can be exploited by creating a new dMSA linked to any user or computer account without requiring direct access to the original account. Researchers found that 91% of examined environments had users outside the Domain Admin group with the necessary permissions to execute this attack. Microsoft has been notified and is working on a patch, while organizations are advised to restrict dMSA creation to trusted administrators and enhance their security measures.

Winsage

May 22, 2025

BadSuccessor: Unpatched Microsoft Active Directory attack enables domain takeover

The dMSA account in Active Directory manages service accounts with enhanced security and automation. Key attributes include msDS-DelegatedMSAState, which indicates the migration status (unknown, in progress, or completed), and msDS-ManagedAccountPrecededByLink, which identifies the superseded account. The msDS-GroupMSAMembership attribute specifies authorized principals for authentication as the dMSA account. After migration, systems using the old service account receive a notification from the Domain Controller that the previous account is disabled, along with a KERB-SUPERSEDED-BY-USER field pointing to the new dMSA. The Key Distribution Center (KDC) within the Kerberos protocol validates user identities and grants access based on permissions, ensuring secure network resource access.

Winsage

May 21, 2025

New Windows Server 2025 Attack Compromises Any Active Directory User

A significant security flaw, named BadSuccessor, has been discovered in Windows Server 2025, posing a serious risk to Active Directory users. This privilege escalation vulnerability allows attackers to compromise any user in Active Directory and is alarmingly easy to exploit, requiring only basic permissions on any organizational unit. Currently, no patch is available for this vulnerability. In 91% of environments examined, users outside the domain admins group had the necessary permissions to execute the attack. The exploit leverages the delegated Managed Service Account (dMSA) feature, enabling attackers to take control of any principal within the domain. Microsoft has rated the vulnerability as moderate severity and plans to address it in a future update, noting that elevated user permissions are required for successful exploitation. Organizations are advised to identify and eliminate unnecessary permissions to mitigate potential threats.

Winsage

May 21, 2025

Active Directory DMSA Attack Detailed By Researchers

The delegated Managed Service Account (dMSA) feature in Windows Server 2025 has a privilege escalation vulnerability that allows attackers to compromise any user in an Active Directory (AD) environment. Research by Yuval Gordon revealed that in 91% of examined environments, users outside the domain admins group had the necessary permissions to exploit this vulnerability. The attack can be executed with benign permissions on any organizational unit (OU) and does not require actual migration of accounts. Gordon's technique, called “BadSuccessor,” enables an attacker controlling a dMSA object to inherit the permissions and keys of any user, including those with high privileges. Microsoft has acknowledged the vulnerability but categorized it as a Moderate severity issue. Akamai recommends limiting the creation of dMSAs and tightening permissions until a patch is released.

Winsage

May 6, 2025

Microsoft pushes fix for Windows 11 update 0x80240069 errors

Microsoft has resolved an issue that affected the delivery of Windows 11 24H2 feature updates via Windows Server Update Services (WSUS) after the installation of the April 2025 security updates. Users reported upgrade problems, specifically encountering error code 0x80240069 during attempts to update from Windows 11 23H2 or 22H2. The update complications primarily impact enterprise environments using WSUS, while home users are less likely to experience these issues. Microsoft is rolling out a fix through Known Issue Rollback (KIR) for enterprise-managed devices, requiring IT administrators to implement the KIR Group Policy on affected endpoints. Additionally, Microsoft is addressing a separate issue where some PCs were upgraded to Windows 11 despite Intune policies preventing such upgrades.

Winsage

April 16, 2025

Microsoft warns of blue screen crashes caused by April updates

Microsoft has warned customers about potential system failures due to a blue screen error (secure kernel fatal error) following the installation of Windows updates since March, specifically the KB5055523 April cumulative update and the KB5053656 March preview update, affecting Windows 11, version 24H2. Users may experience crashes and a blue screen exception with the code 0x18B. Microsoft is working on a solution and has implemented a Known Issue Rollback (KIR) to reverse the problematic updates, which will automatically reach affected devices within 24 hours. Affected users are advised to restart their devices. For enterprise-managed devices, administrators must install the KIR Group Policy specific to their Windows version to resolve the issue, requiring a device restart. Further assistance is available on the Microsoft support website. Additionally, Microsoft has released emergency updates for local audit logon policies in Active Directory Group Policy and alerted administrators about potential inaccessibility of Windows Server 2025 domain controllers post-restart.

Winsage

April 15, 2025

Windows Server 2025 may lose DC connectivity after restart

Microsoft has warned about potential accessibility issues with Windows Server 2025 domain controllers after a restart, where affected servers revert to the default firewall profile, disrupting applications and services. A temporary workaround involves manually restarting the network adapter on the impacted servers using the PowerShell command: Restart-NetAdapter *. This workaround needs to be reapplied after each restart of the domain controller, and Microsoft recommends setting up a scheduled task to automate this process. Windows Server 2025, launched earlier this year, introduced new features and security enhancements but has faced previous issues, including freezing Remote Desktop sessions and accidental upgrades from Windows Server 2022. Developers are currently working on a permanent solution for the domain controller issue.

Winsage

April 14, 2025

Windows Server 2025 Restart Bug Breaks Connection with Active Directory Domain Controller

Microsoft has warned IT administrators about a significant issue affecting Windows Server 2025 domain controllers, which may struggle to manage network traffic after a system restart. This problem arises because the domain controllers revert to the standard firewall profile instead of the required domain firewall profile, leading to potential inaccessibility on the domain network, application failures, and open ports that could pose security risks. The issue specifically affects Windows Server 2025 systems with the Active Directory Domain Services role, while client systems and earlier server versions remain unaffected. To address this, Microsoft recommends a temporary workaround: manually restarting the network adapter using PowerShell with the command Restart-NetAdapter * after each reboot. Administrators are advised to create a scheduled task for automation, monitor domain controllers for disruptions, and minimize unnecessary restarts. Microsoft is working on a permanent fix, with an update expected in the future.

Winsage

April 14, 2025

Windows Server 2025 domain controllers may lose connectivity after reboot, says Microsoft

Microsoft has alerted IT administrators about potential connectivity issues with Windows Server 2025 domain controllers after a restart, which may lead to network disruptions and unauthorized access. Applications and services relying on these domain controllers could fail or become unreachable. IT administrators are advised to exercise caution when planning server restarts.