CVE-2026-62886: CVE-2026-62886: .NET Elevation of Privilege Vulnerability via Native Heap Buffer Overflow

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CVE-2026-62886: .NET Elevation of Privilege Vulnerability via Native Heap Buffer Overflow

Vulnerability ID: CVE-2026-62886
CVSS Score: 7.8
Published: 2026-08-11

An integer overflow or wraparound vulnerability (CWE-190) in the native layer of the .NET runtime allows local unauthenticated attackers to corrupt the native heap, leading to a heap-based buffer overflow (CWE-122) and local privilege escalation.

TL;DR

An integer overflow in the native memory allocation logic of the .NET runtime allows a local attacker to trigger a heap-based buffer overflow, leading to local privilege elevation via crafted application inputs.

Technical Details

CWE ID: CWE-190, CWE-122
Attack Vector: Local (AV:L)
CVSS Severity: 7.8 (High)
Exploit Status: None
KEV Status: Not Listed

Affected Systems

.NET 10.0 Runtime and SDK
.NET 9.0 Runtime and SDK
.NET 8.0 Runtime and SDK
Microsoft Visual Studio 2022
Microsoft Visual Studio 2026
.NET 10.0: >= 10.0.0 and < 10.0.11 (Fixed in: 10.0.11)
.NET 9.0: >= 9.0.0 and < 9.0.19 (Fixed in: 9.0.19)
.NET 8.0: >= 8.0.0 and < 8.0.30 (Fixed in: 8.0.30)

Mitigation Strategies

Update .NET runtimes and SDKs to patched releases
Apply least-privilege principles to .NET services and tools
Enforce execution control policies on endpoints to prevent untrusted .NET binaries from running

Remediation Steps:

Identify all systems running vulnerable versions of .NET and Visual Studio.
Deploy updates for .NET 8.0, 9.0, and 10.0 runtime packages.
Rebuild and redeploy applications bundling custom native dependencies with bounds-checking enabled.