Heap-based buffer overflow in Microsoft products - CVE-2026-69522

Vulnerability identifier: #VU147767

CSH Severity: High

CVSS v4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-69522

CWE-ID: CWE-122

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to a heap-based buffer overflow in Visual Studio when a user opens a specially crafted file. A remote attacker can provide a specially crafted file to execute arbitrary code.

.NET
Visual Studio
Microsoft .NET Framework

Install security update from vendor's website.

.NET - addressed in versions 8.0.31, 9.0.20
Visual Studio - update to 17.14.40
Microsoft .NET Framework - addressed in versions 2.0.50727.8984 & 3.0.30729.8980 & 4.7.4145.0, 2.0.50727.9070 & 3.0.30729.9068 & 4.7.4145.0, 2.0.50727.9070 & 3.0.30729.9068 & 4.8.4806.0, 2.0.50727.9183 & 3.0.30729.9169 & 4.8.4806.0, 2.0.50727.9183 & 3.0.30729.9169 & 4.8.9346.0, 2.0.50727.9183 & 3.0.30729.9169 & 4.8.9347.0, 4.7.4145.0, 4.8.4806.0, 10.0.12

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-69522

• Multiple vulnerabilities in Visual Studio