NuGet · System.Security.Cryptography.Xml
Microsoft Security Advisory CVE-2026-47304 – .NET Security Feature Bypass Vulnerability
Microsoft is releasing this security advisory to provide information about a vulnerability in .NET XML Encryption (System.Security.Cryptography.Xml). This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
A security feature bypass vulnerability exists in the XML encryption implementation (EncryptedXml) in .NET 8, .NET 9, and .NET 10. An attacker could exploit this vulnerability to bypass encryption protections and access encrypted data.
Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/412.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:CThe vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below
| Package name | Affected version | Patched version |
|---|---|---|
| System.Security.Cryptography.Xml | >= 10.0.0, <= 10.0.9 | 10.0.10 |
| Package name | Affected version | Patched version |
|---|---|---|
| System.Security.Cryptography.Xml | >= 9.0.0, <= 9.0.17 | 9.0.18 |
| Package name | Affected version | Patched version |
|---|---|---|
| System.Security.Cryptography.Xml | >= 8.0.0, <= 8.0.3 | 8.0.4 |
If using a package listed in affected packages, you're exposed to the vulnerability.
To update the System.Security.Cryptography.Xml NuGet package, use one of the following methods:
NuGet Package Manager UI in Visual Studio:
Using the NuGet Package Manager Console in Visual Studio:
Update-Package -Id System.Security.Cryptography.Xml
Using the .NET CLI (Command Line Interface):
dotnet add package System.Security.Cryptography.Xml
Once you have updated the nuget package reference you must recompile and deploy your application. Additionally we recommend you update your runtime and/or SDKs, but it is not necessary to patch the vulnerability.
If you have found a potential security issue in a supported version of .NET, please report it to the Microsoft Security Response Center (MSRC) via the MSRC Researcher Portal. Further information can be found in the MSRC Report an Issue FAQ.
Security reports made through MSRC may qualify for the Microsoft .NET Bounty. Details of the Microsoft .NET Bounty Program including terms and conditions are at https://aka.ms/corebounty.
You can ask questions about this issue on GitHub in the .NET GitHub organization. The main repos are located at https://github.com/dotnet/runtime. The Announcements repo (https://github.com/dotnet/Announcements) will contain this bulletin as an issue and will include a link to a discussion issue. You can ask questions in the linked discussion issue.
The information provided in this advisory is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
Levi Broderick with Microsoft
V1.0 (July 14, 2026): Advisory published.
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