Microsoftは、Windowsにおいて26年もの間デフォルトでサポートしてきた暗号化方式「RC4」を、ついに廃止することを決定しました。長年にわたりサイバー攻撃の標的となってきたこの古い技術を排除することで、Windows環境の安全性を根本から高める狙いがあります ...

この記事は会員限定です。会員登録すると全てご覧いただけます。 Microsoftは2025年12月3日（現地時間）、Kerberos認証において、暗号方式RC4（Rivest Cipher 4）を段階的に廃止する方針を公式ブログで明らかにした。 発表によれば、2026年半ばまでに「Windows Server 2008 ...

Although RC4 encryption should already be a thing of the past, it is still used sporadically today. Microsoft has now announced that it will remove Rivest Cipher 4 from Kerberos. This is intended to ...

RC4 has been exploited in high-profile attacks across enterprise Windows networks Kerberoasting exploits weaknesses in Active Directory, allowing attackers to perform offline password cracking ...

About time: Microsoft introduced support for the RC4 stream cipher in Windows 2000 as the default authentication algorithm for the Active Directory services. The system has been insecure for even ...

Microsoft is officially moving to shut the door on RC4 - a legacy cryptographic cipher that has quietly persisted inside Windows authentication environments for decades - and forcing organizations to ...

Microsoft released optional security updates Tuesday for various versions of the .NET Framework that prevent the RC4 encryption algorithm from being used in TLS (Transport Layer Security) connections.

In the Windows Release Health Message Center, Microsoft explains that the software fix for a security vulnerability in Kerberos initiates the hardening of Kerberos with RC4. The vulnerability itself ...