Out-of-bounds read in Microsoft Windows and Windows Server - CVE-2025-29956

Vulnerability identifier: #VU109053

CSH Severity: Medium

CVSS v4: 5.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2025-29956

CWE-ID: CWE-125

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition in Windows SMB. A remote user can trick a victim to open an SMB share folder trigger an out-of-bounds read error and read contents of memory on the system.

Microsoft Windows
Windows Server

Install updates from vendor's website.

Microsoft Windows - addressed in versions 10 21H2 10.0.19044.5854, 10 22H2 10.0.19045.5854, 10 1507 10.0.10240.21014, 10 1607 10.0.14393.8066, 10 1809 10.0.17763.7314, 11 22H2 10.0.22621.5335, 11 23H2 10.0.22631.5335, 11 24H2 10.0.26100.3981, 11 24H2 10.0.26100.4061
Windows Server - addressed in versions 2008 R2 6.1.7601.27729, 2008 6.0.6003.23279, 2012 R2 6.3.9600.22577, 2012 6.2.9200.25475, 2016 10.0.14393.8066, 2019 10.0.17763.7314, 2022 23H2 10.0.25398.1611, 2022 10.0.20348.3630, 2022 10.0.20348.3692, 2025 10.0.26100.3981, 2025 10.0.26100.4061

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2025-29956

• Out-of-bounds read in Microsoft Windows SMB