# CVE-2026-50527: Microsoft .NET Framework stack-based buffer overflow

Source: https://junglewise.ai/threats/cve-2026-50527-microsoft-net-framework-stack-based-buffer-overflow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-14. Updated: 2026-07-21  
License: CC BY 4.0 with a link back

CVE-2026-50527 · Severity: high · CVSS 7.5 · Published 2026-07-14

A security vulnerability has been identified in a Microsoft .NET component used for processing encrypted XML data. An attacker could exploit this flaw to crash an application or service, leading to a denial of service. This affects developers using .NET 8, 9, and 10 who utilize the System.Security.Cryptography.Xml package.

Technologies: [Microsoft .NET Framework](https://junglewise.ai/threats/technologies/net-framework), [System.Security.Cryptography.Xml (NuGet)](https://junglewise.ai/threats/technologies/system-security-cryptography-xml). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft), [NuGet](https://junglewise.ai/threats/vendors/nuget).

## Quick answers

**Is CVE-2026-50527 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-50527 being exploited in the wild.

**How severe is CVE-2026-50527?** High severity, with a CVSS score of 7.5, published 14 July 2026.

**Which products and versions are affected?** Microsoft .NET Framework < 2.0.50727.8983 & 3.0.30729.8978; System.Security.Cryptography.Xml (NuGet) ECOSYSTEM:introduced=10.0.0,fixed=10.0.10.

**Is there a fix for CVE-2026-50527?** Yes. System.Security.Cryptography.Xml (NuGet): upgrade to 10.0.10 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-50527 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-50527?** Check whether you run Microsoft .NET Framework or System.Security.Cryptography.Xml (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.

## How to fix

- System.Security.Cryptography.Xml (NuGet): upgrade to 10.0.10 or later

  ```sh
  dotnet add package System.Security.Cryptography.Xml --version 10.0.10
  ```


## Technical details

A denial of service vulnerability exists in the EncryptedXml implementation within the System.Security.Cryptography.Xml package for .NET 8, 9, and 10. The issue is classified as a stack-based buffer overflow (CWE-121) resulting from improper validation of crafted encrypted XML input. An unauthenticated remote attacker can exploit this by providing malicious XML data, causing the application to crash. Microsoft has released patched versions of the NuGet package (8.0.29, 9.0.18, and 10.0.10) to address this flaw.

## Affected products

- Microsoft System.Security.Cryptography.Xml >= 8.0.0, <= 8.0.28; >= 9.0.0, <= 9.0.17; >= 10.0.0, <= 10.0.9

## Identifiers

- CVE-2026-50527
- GHSA-mmjf-rqrv-855v

## Timeline

- 2026-07-14: disclosed
- 2026-07-14: patched
- 2026-07-21: advisory

## References

- [https://github.com/dotnet/runtime/security/advisories/GHSA-mmjf-rqrv-855v](https://github.com/dotnet/runtime/security/advisories/GHSA-mmjf-rqrv-855v)
- [https://github.com/dotnet/announcements/issues/416](https://github.com/dotnet/announcements/issues/416)
- [https://github.com/dotnet/runtime/issues/130712](https://github.com/dotnet/runtime/issues/130712)
- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50527](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50527)
- [https://api.github.com/repos/dotnet/runtime/security-advisories/GHSA-mmjf-rqrv-855v](https://api.github.com/repos/dotnet/runtime/security-advisories/GHSA-mmjf-rqrv-855v)

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