Microsoft Visual Studio heap buffer overflow in DiaSymReader

Severity: high · CVSS 8.8 · Published 2026-09-08

Microsoft Visual Studio contains a heap buffer overflow bug in a debugging symbol reader component that could allow an attacker to execute malicious code on a developer's machine over the network. This affects the DiaSymReader.Native library used by Visual Studio for parsing debug information. A successful exploit could give an attacker complete control over the affected system, compromising development environments and potentially sensitive source code or intellectual property.

Technologies: Microsoft DiaSymReader.Native, Microsoft.DiaSymReader.Native (NuGet). Vendors: Microsoft, NuGet.

Quick answers

Is This vulnerability exploited in the wild?
No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?
High severity, with a CVSS score of 8.8, published 8 September 2026.
Which products and versions are affected?
Microsoft DiaSymReader.Native >= 17.10.0-beta1.24272.1, <= 18.9.0-beta1.26405.1; Microsoft.DiaSymReader.Native (NuGet) >= 17.10.0-beta1.24272.1, <= 18.9.0-beta1.26405.1.
Is there a fix for This vulnerability?
A patch was published on 2026-09-08: Patch version 18.9.0-beta1.26405.2 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?
It is attacked over the network, in a software library.
Am I affected?
Check whether you run Microsoft DiaSymReader.Native or Microsoft.DiaSymReader.Native (NuGet) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

This is a heap-based buffer overflow vulnerability (CWE-122) in Microsoft's DiaSymReader.Native component, which is responsible for reading debug symbol information in Visual Studio. The vulnerability can be exploited over a network (AV:N) with low attack complexity (AC:L), requiring no special privileges (PR:N) but does require user interaction (UI:R). An attacker can exploit this to achieve arbitrary code execution with high impact on confidentiality, integrity, and availability. The vulnerable version range is Microsoft.DiaSymReader.Native >= 17.10.0-beta1.24272.1 through <= 18.9.0-beta1.26405.1. Microsoft has released a patch in version 18.9.0-beta1.26405.2. Note: This advisory was withdrawn as a duplicate of GHSA-2j8r-3c22-8565.

Affected products

  • Microsoft Microsoft.DiaSymReader.Native >= 17.10.0-beta1.24272.1, <= 18.9.0-beta1.26405.1

Timeline

  • 2026-09-08: disclosed
  • 2026-09-08: patched: Patch version 18.9.0-beta1.26405.2 released

References

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