CVE-2026-20818 | Windows Kernel Information Disclosure Vulnerability

Insertion of sensitive information into log file in Windows Kernel allows an unauthorized attacker to disclose information locally.

Published: 2026-01-13 Last update: 2026-01-14 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-20818 is rated Moderate Risk (42.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.69%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-20818

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.04% 0.69% +0.65%
2 2026-06-11 0.06% 0.04% -0.02%
3 2026-05-15 0.06%

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-20818

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.2 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.5 3.6 [email protected]

Weakness enumeration for CVE-2026-20818

Affected software / configurations for CVE-2026-20818

Vendor Product Version Raw CPE
microsoft windows_server_2016 < 10.0.14393.8783 cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*
microsoft windows_server_2019 < 10.0.17763.8276 cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*
microsoft windows_server_2022 < 10.0.20348.4648 cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*
microsoft windows_server_2022_23h2 < 10.0.25398.2092 cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:*
microsoft windows_server_2025 < 10.0.26100.7623 cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*

References for CVE-2026-20818

cvelogic Threat Intelligence