CVE-2026-40397
published 2026-05-12CVE-2026-40397: Heap-based buffer overflow in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally.
PriorityP348high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.27%
19.2th percentile
Heap-based buffer overflow in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally.
Affected
29 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | windows_10_1607 | < 10.0.14393.9140 | 10.0.14393.9140 |
| microsoft | windows_10_1809 | < 10.0.17763.8755 | 10.0.17763.8755 |
| microsoft | windows_10_21h2 | < 10.0.19044.7291 | 10.0.19044.7291 |
| microsoft | windows_10_22h2 | < 10.0.19045.7291 | 10.0.19045.7291 |
| microsoft | windows_10_version_1607 | >= 10.0.14393.0 < 10.0.14393.9140 | 10.0.14393.9140 |
| microsoft | windows_10_version_1809 | >= 10.0.17763.0 < 10.0.17763.8755 | 10.0.17763.8755 |
| microsoft | windows_10_version_21h2 | >= 10.0.19044.0 < 10.0.19044.7291 | 10.0.19044.7291 |
| microsoft | windows_10_version_22h2 | >= 10.0.19045.0 < 10.0.19045.7417 | 10.0.19045.7417 |
| microsoft | windows_11_23h2 | < 10.0.22631.7079 | 10.0.22631.7079 |
| microsoft | windows_11_24h2 | < 10.0.26100.8390 | 10.0.26100.8390 |
| microsoft | windows_11_25h2 | < 10.0.26200.8390 | 10.0.26200.8390 |
| microsoft | windows_11_26h1 | < 10.0.28000.2113 | 10.0.28000.2113 |
| microsoft | windows_11_version_23h2 | >= 10.0.22631.0 < 10.0.22631.7079 | 10.0.22631.7079 |
| microsoft | windows_11_version_23h2 | >= 10.0.22631.0 < 10.0.22631.7219 | 10.0.22631.7219 |
| microsoft | windows_11_version_24h2 | >= 10.0.26100.0 < 10.0.26100.8457 | 10.0.26100.8457 |
| microsoft | windows_11_version_25h2 | >= 10.0.26200.0 < 10.0.26200.8457 | 10.0.26200.8457 |
| microsoft | windows_11_version_26h1 | >= 10.0.28000.0 < 10.0.28000.2113 | 10.0.28000.2113 |
| microsoft | windows_server_2012 | — | — |
| microsoft | windows_server_2012 | >= 6.2.9200.0 < 6.2.9200.26079 | 6.2.9200.26079 |
| microsoft | windows_server_2012_r2 | >= 6.3.9600.0 < 6.3.9600.23181 | 6.3.9600.23181 |
| microsoft | windows_server_2016 | < 10.0.14393.9140 | 10.0.14393.9140 |
| microsoft | windows_server_2016 | >= 10.0.14393.0 < 10.0.14393.9140 | 10.0.14393.9140 |
| microsoft | windows_server_2019 | < 10.0.17763.8755 | 10.0.17763.8755 |
| microsoft | windows_server_2019 | >= 10.0.17763.0 < 10.0.17763.8755 | 10.0.17763.8755 |
| microsoft | windows_server_2022 | < 10.0.20348.5074 | 10.0.20348.5074 |
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VulDB
Microsoft Windows up to Server 2025 Common Log File System Driver integer underflow
vuldb·2026-05-12
CVE-2026-40397 [CRITICAL] Microsoft Windows up to Server 2025 Common Log File System Driver integer underflow
A vulnerability, which was classified as critical, has been found in Microsoft Windows. This affects an unknown part of the component Common Log File System Driver. Performing a manipulation results in integer underflow.
This vulnerability is cataloged as CVE-2026-40397. The attack must be initiated from a local position. There is no exploit available.
It is advisable to upgrade the affected component.
GHSA
GHSA-864v-w6fx-r2g4: Integer underflow (wrap or wraparound) in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally
ghsa_unreviewed·2026-05-12
CVE-2026-40397 [HIGH] CWE-191 GHSA-864v-w6fx-r2g4: Integer underflow (wrap or wraparound) in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally
Integer underflow (wrap or wraparound) in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally.
No detection rules found.
No public exploits indexed.
Rapid7
Patch Tuesday - May 2026
blogs_rapid7·2026-05-13·CVSS 10.0
CVE-2026-41089 [CRITICAL] Patch Tuesday - May 2026
Microsoft is publishing 137 vulnerabilities on May 2026 Patch Tuesday . Microsoft is not aware of exploitation in the wild or public disclosure for any of these vulnerabilities. So far this month, Microsoft has provided patches to address 133 browser vulnerabilities, which are not included in the Patch Tuesday count above.
## Windows Netlogon: critical RCE
Anyone responsible for securing a domain controller should prioritize remediation of CVE-2026-41089 , which is a critical stack-based buffer overflow in Windows Netlogon with a CVSS v3 base score of 9.8. Exploitation leads to execution in the context of the Netlogon service, so that’s SYSTEM privileges on the domain controller. For most pentesters, that’s the point at which the customer report more or less writes itself. No privileges
Qualys
Microsoft and Adobe Patch Tuesday, May 2026 Security Update Review
blogs_qualys·2026-05-12
CVE-2026-40364 Microsoft and Adobe Patch Tuesday, May 2026 Security Update Review
## Table of Contents
Microsoft Patch Tuesday forMay2026
Adobe Patches for May 2026
Critical Severity Vulnerabilities Patched inMayPatch Tuesday Edition
Other Microsoft Vulnerability Highlights
Microsoft Release Summary
Qualys Monthly Webinar Series
May 2026’s Patch Tuesday arrives with Microsoft addressing a fresh set of vulnerabilities across its ecosystem, reinforcing the ongoing need for timely patching in an increasingly threat-heavy landscape. Here’s a quick breakdown of what you need to know.
## Microsoft Patch Tuesday for May 2026
This month’s release addresses 137 vulnerabilities, including 30 critical and 103 important-severity vulnerabilities.
In this month’s updates, Microsoft has not addressed any publicly disclosed zero-day vulnerability.
Microsoft has addressed 128
Talos
Microsoft Patch Tuesday for May 2026 — Snort rules and prominent vulnerabilities
blogs_talos·2026-05-12·CVSS 7.5
CVE-2026-32161 [HIGH] Microsoft Patch Tuesday for May 2026 — Snort rules and prominent vulnerabilities
## Microsoft Patch Tuesday for May 2026 — Snort rules and prominent vulnerabilities
By Jaeson Schultz
Microsoft has released its monthly security update for May 2026, which includes 137 vulnerabilities affecting a range of products, including 31 that Microsoft marked as “critical”.
In this month's release, Microsoft has not observed any of the included vulnerabilities being actively exploited in the wild. Out of 31 "critical" entries, 16 are remote code execution (RCE) vulnerabilities in Microsoft Windows services and applications including Microsoft Office, Microsoft Word, Windows Native WiFi Miniport Driver, Azure, Office for Android, Microsoft Dynamics 365, Windows GDI, Microsoft SharePoint, Windows Graphics Component, Windows Netlogon, and Windows DNS Client.
CVE-2026-32161 is a cr
Sans Isc
Microsoft May 2026 Patch Tuesday, (Tue, May 12th)
blogs_sans_isc·2026-05-12·CVSS 4.3
CVE-2026-41103 [MEDIUM] Microsoft May 2026 Patch Tuesday, (Tue, May 12th)
Microsoft May 2026 Patch Tuesday
Published: 2026-05-12. Last Updated: 2026-05-12 18:29:36 UTC
by Johannes Ullrich (Version: 1)
0 comment(s)
Today's Microsoft patch Tuesday fixes 137 different vulnerabilities. In addition, the update addresses 137 Chromium-related issues affecting Microsoft Edge.
There are no already disclosed or already exploited vulnerabilities included in today's patches. I removed the Chromium issues from the table below and included only the 137 Microsoft issues to make it more readable.
Note that issues related to Microsoft Azure are labeled as "no customer action required.
Significant Vulnerabilities of interest:
CVE-2026-41103: This vulnerability affects the Microsoft SSO Plugin for Jira & Confluence. Exploitation could lead to an elevation of privileges. Wit
2026-05-12
Published