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CVE-2026-42837 Microsoft CVE debrief

CVE-2026-42837 is a HIGH severity vulnerability in the Windows Projected File System Filter Driver. A buffer over-read issue exists that allows an authorized attacker to elevate privileges locally. The vulnerability has a CVSS score of 7.8.

Vendor
Microsoft
Product
Windows Projected File System Filter Driver
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-09
Original CVE updated
2026-06-11
Advisory published
2026-06-09
Advisory updated
2026-06-11

Who should care

Administrators and users of affected Microsoft Windows systems should prioritize patching this vulnerability to prevent local privilege escalation attacks.

Technical summary

The vulnerability exists in the Windows Projected File System Filter Driver and is caused by a buffer over-read issue. This allows an authorized attacker to elevate privileges locally.

Defensive priority

HIGH

Recommended defensive actions

  • Apply patches from Microsoft as soon as possible.
  • Review and update system configurations to ensure proper protections are in place.
  • Monitor systems for unusual activity that could indicate exploitation attempts.

Evidence notes

The CVE-2026-42837 vulnerability was published on 2026-06-09 and modified on 2026-06-11. It affects various versions of Microsoft Windows.

Official resources

CVE-2026-42837 was published on 2026-06-09T17:17:09.453Z and modified on 2026-06-11T16:51:47.073Z.