Security

Microsoft rolled out emergency updates to fix Windows Server auth failures

Microsoft has released out-of-band security updates to address authentication issues affecting Windows Server.

Microsoft has released out-of-band updates to fix authentication failures related to Kerberos delegation scenarios impacting Domain Controllers (DC) running Windows Server.

These issues impacts Windows Server 2019 and lower versions, including Windows Server 2016, Windows Server 2012 R2, Windows Server 2012, Windows Server 2008 R2 SP1, and Windows Server 2008 SP2.

Below is the list of out-of-band updates released by the IT giant:

“Addresses a known issue that might cause authentication failures related to Kerberos tickets you acquired from Service for User to Self (S4U2self). This issue occurs after you install the November 9, 2021 security updates on domain controllers (DC) that are running Windows Server.” warns Microsoft.

In order to install the emergency updates, administrators should download the standalone update package from the Microsoft Update Catalog.

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Pierluigi Paganini

(SecurityAffairs – hacking, Operation Cyclone)

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Pierluigi Paganini

Pierluigi Paganini is member of the ENISA (European Union Agency for Network and Information Security) Threat Landscape Stakeholder Group and Cyber G7 Group, he is also a Security Evangelist, Security Analyst and Freelance Writer. Editor-in-Chief at "Cyber Defense Magazine", Pierluigi is a cyber security expert with over 20 years experience in the field, he is Certified Ethical Hacker at EC Council in London. The passion for writing and a strong belief that security is founded on sharing and awareness led Pierluigi to find the security blog "Security Affairs" recently named a Top National Security Resource for US. Pierluigi is a member of the "The Hacker News" team and he is a writer for some major publications in the field such as Cyber War Zone, ICTTF, Infosec Island, Infosec Institute, The Hacker News Magazine and for many other Security magazines. Author of the Books "The Deep Dark Web" and “Digital Virtual Currency and Bitcoin”.

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