Local service interruption via VMSwitch buffer miscalculation
Published Jun 9, 2026 · Updated Jun 9, 2026
Incorrect buffer-size calculation in Windows VMSwitch allows local users to interrupt service on affected Windows systems. Microsoft identifies VMSwitch as the locus but has not published the specific calculation, input, or code path that produces the incorrect buffer size. Exploitation requires local low-privileged access and no user interaction; the reported consequence is an availability-only service interruption.
Summary
What happened
Incorrect buffer-size calculation in Windows VMSwitch allows local users to interrupt service on affected Windows systems. Microsoft identifies VMSwitch as the locus but has not published the specific calculation, input, or code path that produces the incorrect buffer size. Exploitation requires local low-privileged access and no user interaction; the reported consequence is an availability-only service interruption.
The record
- CVE
- CVE-2026-42915
- Published
- Jun 9, 2026
- Updated
- Jun 9, 2026
- Vendor
- Microsoft
- Product
- Windows Server 2025 (Server Core installation)
- Classifications
- CWE-131, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 9, 2026CVE publishedPublication date reported by the CVE source.
- Jun 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=10.0.26100.0 <10.0.26100.32995
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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