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Windows Defender zero-day blocks antivirus updates

A newly disclosed Windows Defender exploit prevents Microsoft's antivirus from updating, potentially leaving systems unprotected.

· 1 min read · 4 sources

Security researcher Abdelhamid Naceri, also known as Nightmare Eclipse, has published another Windows Defender zero-day exploit. The flaw prevents Microsoft's antivirus from receiving updates, which could leave systems vulnerable to new threats while the update mechanism is disrupted.

The exploit was released over the weekend, according to the report. No details about a patch or official mitigation were mentioned in the source, and it is unclear whether Microsoft has acknowledged the issue yet.

This is not the first time Naceri has disclosed a Defender flaw; the researcher has previously released similar exploits. The repeated disclosures highlight ongoing concerns about the security of Microsoft's built-in antivirus product.

Sources · 4

  1. 01NightmareEclipse's latest zero-day leaves Microsoft Defender stuck in the pastThe Register
  2. 02Researcher Drops BigDiskBuster Zero-Day PoC That Blocks Microsoft Defender UpdatesThe Hacker News
  3. 03Nightmare Eclipse Drops New Microsoft Defender Exploit After Revealing IdentitySecurityWeek
  4. 04New Windows Defender zero-day blocks Microsoft antivirus updatesBleepingComputer

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