Vulnerability · Published Oct 13, 2026 · Assigned by microsoft

CVE-2026-83856Windows Event Logging Service Remote Code Execution Vulnerability

High 7.5

In plain English

A high-severity out-of-bounds read in Windows 11 version 23H2 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 50% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.6%top 49.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Out-of-bounds read in Windows Event Logging Service allows an unauthorized attacker to execute code over a network.

Affected products (as reported)

VendorProductVersions
Microsoft Windows 11 version 23H2 10.0.22631.0 – before 10.0.22631.7652
Microsoft Windows 11 Version 23H2 10.0.22631.0 – before 10.0.22631.7652
Microsoft Windows 11 Version 24H2 10.0.26100.0 – before 10.0.26100.9711
Microsoft Windows 11 Version 25H2 10.0.26200.0 – before 10.0.26200.9711
Microsoft Windows 11 version 26H1 10.0.28000.0 – before 10.0.28000.3231
Microsoft Windows 11 Version 26H2 10.0.26300.0 – before 10.0.26300.9711
Microsoft Windows Server 2022 10.0.20348.0 – before 10.0.20348.5761
Microsoft Windows Server 2025 10.0.26100.0 – before 10.0.26100.33650
Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.0 – before 10.0.26100.33650

Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

References