Vulnerability in Microsoft Windows 10 1809
CVE-2026-58638
Missing cryptographic step in Windows Boot Loader allows an authorized attacker to bypass a security feature locally.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.0 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.002 (13.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 13th percentile — 13.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Microsoft Windows 10 1809
- Microsoft Windows 10 21h2
- Microsoft Windows 10 22h2
- Microsoft Windows 10 Version 1809 — versions 10.0.17763.0
- Microsoft Windows 10 Version 21h2 — versions 10.0.19044.0
- Microsoft Windows 10 Version 22h2 — versions 10.0.19045.0
- Microsoft Windows 11 23h2
- Microsoft Windows 11 24h2
- Microsoft Windows 11 25h2
- Microsoft Windows 11 26h1
Weakness classification (CWE)
References
- Windows Boot Loader Security Feature Bypass Vulnerability (vendor-advisory, Patch, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-58638?
- CVE-2026-58638 is a medium-severity vulnerability in Microsoft Windows 10 1809, classified under Missing Cryptographic Step. CVSS score: 6.0/10. Published 2026-07-14.
- How severe is CVE-2026-58638?
- Medium severity. CVSS v3 base score is 6.0 out of 10.