Out-of-Bounds Read in Windows NTFS

Publication date: 2026-09-08

Last updated on: 2026-09-24

Assigner: Microsoft Corporation

Description

Out-of-bounds read in Windows NTFS allows an unauthorized attacker to elevate privileges locally.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-09-08

Last Modified

2026-09-24

Generated

2026-09-29

AI Q&A

2026-09-10

EPSS Evaluated

2026-09-27

NVD

CVE-2026-77503

Affected Vendors & Products

Vendor	Product	Version / Range
microsoft	windows_server_2012	r2
microsoft	windows_server_2012	*
microsoft	windows_server_2025	to 10.0.26100.33438 (exc)
microsoft	windows_10_1607	to 10.0.14393.9512 (exc)
microsoft	windows_10_1607	to 10.0.14393.9512 (exc)
microsoft	windows_10_1809	to 10.0.17763.9245 (exc)
microsoft	windows_10_1809	to 10.0.17763.9245 (exc)
microsoft	windows_10_21h2	to 10.0.19044.7725 (exc)
microsoft	windows_10_21h2	to 10.0.19044.7725 (exc)
microsoft	windows_10_21h2	to 10.0.19044.7725 (exc)
microsoft	windows_10_22h2	to 10.0.19045.7725 (exc)
microsoft	windows_10_22h2	to 10.0.19045.7725 (exc)
microsoft	windows_10_22h2	to 10.0.19045.7725 (exc)
microsoft	windows_11_23h2	to 10.0.22631.7582 (exc)
microsoft	windows_11_23h2	to 10.0.22631.7582 (exc)
microsoft	windows_11_24h2	to 10.0.26100.9445 (exc)
microsoft	windows_11_24h2	to 10.0.26100.9445 (exc)
microsoft	windows_11_25h2	to 10.0.26200.9445 (exc)
microsoft	windows_11_25h2	to 10.0.26200.9445 (exc)
microsoft	windows_11_26h1	to 10.0.28000.2954 (exc)
microsoft	windows_11_26h1	to 10.0.28000.2954 (exc)
microsoft	windows_server_2016	to 10.0.14393.9512 (exc)
microsoft	windows_server_2019	to 10.0.17763.9245 (exc)
microsoft	windows_server_2022	to 10.0.20348.5622 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-125	The product reads data past the end, or before the beginning, of the intended buffer.

Attack-Flow Graph

Executive Summary

This is an out-of-bounds read vulnerability in Windows NTFS that allows an unauthorized attacker to elevate their privileges locally. This means an attacker could gain higher access rights than intended, potentially taking control of the system.

Impact Analysis

If exploited, this vulnerability could allow an attacker to gain administrative privileges on your system. This could lead to unauthorized access, data theft, installation of malware, or complete system compromise.

Mitigation Strategies

Apply the latest security updates from Microsoft to patch the NTFS vulnerability. Monitor Microsoft's update guide for patches and install them as soon as available.

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