CVE-2026-42915: Microsoft Windows VMSwitch Denial of Service Vulnerability
Incorrect calculation of buffer size in Windows VMSwitch allows an authorized attacker to deny service locally.
CSIRTS triage
- What
- A denial of service vulnerability exists due to incorrect buffer size calculations in Windows VMSwitch.
- Who is affected
- Authorized users of Microsoft Windows VMSwitch.
- Urgency
- Remediation is medium urgency due to moderate severity and no current exploitation reported.
- Action
- Apply the latest security updates for Windows VMSwitch.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42915
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-429150.38% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 30% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-42915 | coverage & exploitation status | NVD · CVE.org |
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