# CVE-2026-32177: Microsoft .NET heap buffer overflow privilege escalation

Source: https://junglewise.ai/threats/cve-2026-32177-microsoft-net-heap-buffer-overflow-privilege-escalation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-12. Updated: 2026-06-18  
License: CC BY 4.0 with a link back

CVE-2026-32177 · Severity: high · CVSS 7.3 · Published 2026-05-12

A security vulnerability exists in Microsoft .NET and .NET Framework, which are widely used platforms for building and running applications on Windows. An attacker who successfully exploits this flaw could gain higher-level system permissions than they should normally have. This could allow an unauthorized user to take control of an affected system, potentially leading to data theft or further malicious activity.

Technologies: [Microsoft .NET Framework](https://junglewise.ai/threats/technologies/net-framework), [Microsoft Visual Studio 2022](https://junglewise.ai/threats/technologies/visual-studio-2022). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-32177 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-32177 being exploited in the wild.

**How severe is CVE-2026-32177?** High severity, with a CVSS score of 7.3, published 12 May 2026.

**Which products and versions are affected?** Microsoft .NET Framework 3.5, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1; Microsoft Visual Studio 2022 17.12.0 to 17.12.19, 17.14.0 to 17.14.31.

**Is there a fix for CVE-2026-32177?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-32177 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-32177?** Check whether you run Microsoft .NET Framework or Microsoft Visual Studio 2022 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 .NET and .NET Framework due to improper input validation (CWE-20). The vulnerability is triggered when the software handles specially crafted input, leading to an out-of-bounds write (CWE-787). An attacker with local access can exploit this by convincing a user to interact with a malicious application or file (UI:R). Successful exploitation allows the attacker to elevate their privileges to a higher level, potentially gaining full control over the host environment. Microsoft has released security updates to address this issue across affected versions of .NET, .NET Framework, and Visual Studio.

## Affected products

- Microsoft .NET 8.0.0 to 8.0.26, 9.0.0 to 9.0.15, 10.0.0 to 10.0.7
- Microsoft .NET Framework 3.5, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
- Microsoft Visual Studio 2022 17.12.0 to 17.12.19, 17.14.0 to 17.14.31
- Microsoft Visual Studio 2026 18.5.0 to 18.5.2

## Timeline

- 2026-05-12: disclosed
- 2026-05-12: advisory

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-32177](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-32177)

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