VulnSocial

CVE-2026-40407Patch(microsoft / windows_10_1607)

LOWCVSS 7.8 · HIGH

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Patch microsoft windows_10_1607 systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD description

Heap-based buffer overflow in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally.

microsoft CVEsBack to dashboard
1.0/ 10 priority

Sources & remediation

Vendor / third-party advisories
Weakness type (CWE)
CWE-122

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

NONE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • windows_10_1607
  • windows_10_1809
  • windows_10_21h2
  • windows_10_22h2

Threat summary

  • Patch or workaround signal is available
  • 1 mentions across 1 observed day

What's happening

  • Patch or workaround mentioned in 1 signal
  • Technical details provided in 1 signal
  • 1 total mentions across 1 day

Affected systems

Vendors
microsoft
Products
windows_10_1607windows_10_1809windows_10_21h2windows_10_22h2windows_11_23h2windows_11_24h2windows_11_25h2windows_11_26h1windows_server_2012windows_server_2016

2 versions affected across 14 products

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-05-12: 1Patch / Workaround · 2026-05-12: 1Technical Details · 2026-05-12: 105-12
Signal classification1 categories
Patch
1100.0%
Referenced assets1 URL
Full discourse1 post
  • WindowsForum@windowsforum
    Patch

    🚨 CVE-2026-40407 is CLFS doing CLFS things: local heap overflow → privilege escalation. “Not a worm” is cool, but letting low-priv users win? That’s the real problem. #Windows #Security https://windowsforum.com/threads/cve-2026-40407-clfs-privilege-escalation-may-patch-tuesday-fix-explained.417846/?utm_source=x&utm_medium=social&utm_campaign=news_node84 #LocalPrivilegeEscalation #WindowsSecurityUpdates #Cve202640407 https://t.co/Mw83rzFsDA

    Post summary

    The post announces CVE-2026-40407, a local heap overflow that allows privilege escalation, and references a Patch Tuesday fix to mitigate the issue.

    0000046
    1.1K followersView on X
CPE platform detail25 entries

25 of 25 entries

PartVendorProductVersionTarget SWTarget HW
OSmicrosoftwindows_10_1607--x64
OSmicrosoftwindows_10_1607--x86
OSmicrosoftwindows_10_1809--x64
OSmicrosoftwindows_10_1809--x86
OSmicrosoftwindows_10_21h2--arm64
OSmicrosoftwindows_10_21h2--x64
OSmicrosoftwindows_10_21h2--x86
OSmicrosoftwindows_10_22h2--arm64
OSmicrosoftwindows_10_22h2--x64
OSmicrosoftwindows_10_22h2--x86
OSmicrosoftwindows_11_23h2--arm64
OSmicrosoftwindows_11_23h2--x64
OSmicrosoftwindows_11_24h2--arm64
OSmicrosoftwindows_11_24h2--x64
OSmicrosoftwindows_11_25h2--arm64
OSmicrosoftwindows_11_25h2--x64
OSmicrosoftwindows_11_26h1--arm64
OSmicrosoftwindows_11_26h1--x64
OSmicrosoftwindows_server_2012---
OSmicrosoftwindows_server_2012r2--
OSmicrosoftwindows_server_2016---
OSmicrosoftwindows_server_2019---
OSmicrosoftwindows_server_2022---
OSmicrosoftwindows_server_2022_23h2---
OSmicrosoftwindows_server_2025---

Explore more

Back to dashboardmicrosoft CVEswindows_10_1607 vulnerabilities