Description

Microsoft recently identified a vulnerability CVE-2025-29968 in Active Directory Certificate Services (AD CS) caused by improper input validation that could let attackers launch denial-of-service attacks over a network. This flaw, rated as “Important” with a CVSS score of 6.5, affects several versions of Windows Server, including 2022, 2019, 2016, 2012/2012 R2, and 2008/2008 R2. The vulnerability is caused by improper input validation in AD CS, which is a key Windows feature used for managing digital certificates within organizations. If exploited, an attacker with low-level access could make the AD CS service unresponsive, disrupting authentication and secure communications across the organization. This flaw allows an attacker with valid access to disrupt the AD CS service over a network making it unresponsive and potentially interrupting authentication secure communications and other certificate-related functions across an organization. The vulnerability can be exploited remotely with low privileges and does not require any user action. While it does not compromise data confidentiality or integrity but it poses a serious risk to system availability, as it could let a low-level attacker disrupt certificate services for an entire organization. Microsoft has released security updates to fix the AD CS vulnerability (CVE-2025-29968) affecting several versions of Windows Server. IT administrators should install the correct patch for their server version such as KB5058385 for Windows Server 2022, KB5058392 for Windows Server 2019, and KB5058383 for Windows Server 2016. Microsoft has stated that exploiting this vulnerability is unlikely and there have been no reports of it being used in real attacks. The vulnerability was discovered and responsibly reported by an anonymous security researcher, who has been acknowledged by Microsoft. Organizations using Active Directory Certificate Services are advised to apply these updates as part of their regular patch management to stay protected?.