CVE-2026-42904: Windows TCP/IP Elevation of Privilege Vulnerability
Heap-based buffer overflow in Windows TCP/IP allows an unauthorized attacker to elevate privileges over an adjacent network.
CSIRTS triage
- What
- Heap-based buffer overflow in Windows TCP/IP allows an unauthorized attacker to elevate privileges over an adjacent network.
- Who is affected
- Users of Windows TCP/IP on adjacent networks.
- Urgency
- Immediate action is required due to the critical severity and potential for exploitation.
- Action
- Install the security update from Microsoft.
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-2026-42904
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-2026-429040.44% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 35% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-42904 | coverage & exploitation status | NVD · CVE.org |
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