Microsoft Visual Studio heap buffer overflow in DiaSymReader

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

Visual Studio's DiaSymReader component contains a heap buffer overflow that could allow attackers to execute arbitrary code on a developer's machine. An attacker can exploit this remotely by sending a specially crafted request, potentially compromising developer systems and the code they are working on. This could lead to malware installation, theft of source code or credentials, or supply chain attacks.

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A patch was published on 2026-09-09: Patch available in version 18.9.0-beta1.26405.2; advisory withdrawn as duplicate of GHSA-63gh-g2x5-x69v Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.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

A heap-based buffer overflow (CWE-122) exists in Microsoft's DiaSymReader.Native NuGet package, a component used by Visual Studio for debugging symbol processing. The vulnerability is triggered over the network (AV:N) with low attack complexity (AC:L) and no privilege requirement (PR:N), but requires user interaction (UI:R). Affected versions are Microsoft.DiaSymReader.Native >= 17.10.0-beta1.24272.1 through 18.9.0-beta1.26405.1, with a fix available in version 18.9.0-beta1.26405.2. Exploitation allows full code execution (CIA:H) with impact to confidentiality, integrity, and availability. This advisory is marked as withdrawn because it duplicates GHSA-63gh-g2x5-x69v.

Affected products

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

Timeline

  • 2026-09-08: disclosed
  • 2026-09-08: advisory: GitHub Advisory GHSA-4qhr-qf46-fcrx published
  • 2026-09-09: patched: Patch available in version 18.9.0-beta1.26405.2; advisory withdrawn as duplicate of GHSA-63gh-g2x5-x69v

References

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