Use After Free in Microsoft Windows 10 1809

CVE-2026-40415

Use after free in Windows TCP/IP allows an unauthorized attacker to execute code over a network.

Vulnerability class: Use-After-Free

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.007 (51.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 51.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-40415: held from 0.008 to 0.007.

EPSS over last 30 days · oldest: 0.008 · newest: 0.007 · change: -0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-40415?
CVE-2026-40415 is a high-severity vulnerability in Microsoft Windows 10 1809, classified under Use After Free. CVSS score: 8.1/10. Published 2026-05-12.
How severe is CVE-2026-40415?
High severity. CVSS v3 base score is 8.1 out of 10.