Microsoft pushes new Defender update

Microsoft has released Defender Antivirus security intelligence version 1.459.576.0, delivered under the long-running KB2267602 identifier. The package refreshes detection definitions for Microsoft Defender Antivirus and other Microsoft antimalware products on Windows 11, Windows 10, Windows 8.1, and Windows Server. Here is what the update is, how to confirm it, and what to do if it stalls.

What KB2267602 covers

Microsoft says it continually updates security intelligence to cover the latest threats and to tweak detection logic. These definitions work alongside cloud-based protection, which Microsoft describes as AI-enhanced.

How to check your version

You do not need to wait for Windows Update to confirm you are covered. Open Windows Security, go to Virus & threat protection, and select Protection Updates to see the installed security intelligence version. Selecting Check for updates there pulls the latest definitions on demand. If your system already shows 1.459.576.0 or a newer build, your definitions are current, even if the Windows Update history looks inconsistent. Seeing the same KB offered the next day again is normal behavior.

Forcing an update from the command line

Administrators who want to push a refresh can run the Defender command line tool from an elevated prompt. The MpCmdRun.exe utility, found in the Windows Defender folder, accepts the SignatureUpdate switch, which tells Defender to fetch the newest definitions right away. Microsoft's guidance for clearing a stuck cache pairs this with a command that removes old definitions first, so check the documentation before running it across a fleet.

Manual downloads

If automatic updates fail, Microsoft publishes the latest package on its Security Intelligence page, with separate 32-bit, 64-bit, and ARM downloads. Network Inspection System updates are listed separately on the same page, so check your Antimalware Client version before grabbing those. Because Microsoft releases new versions so often, the build you download may already be newer than the one in this article.