.NET Security Feature Bypass Vulnerability Reported
An early warning has been issued regarding a security feature bypass vulnerability in the XML encryption implementation of.NET 8,.NET 9, and.NET 10. This vulnerability, if exploited, could allow an attacker to bypass encryption protections and access encrypted data.
What happened
According to the Microsoft Security Advisory CVE-2026-47304, a security feature bypass vulnerability has been identified in the XML encryption implementation of.NET 8,.NET 9, and.NET 10. This vulnerability reportedly affects the System.Security.Cryptography.Xml component in versions >=10.0.0,<=10.0.9 for.NET 10.0, >=9.0.0,<=9.0.17 for.NET 9.0, and >=8.0.0,<=8.0.3 for .NET 8.0.
The vulnerability appears to allow an attacker to bypass encryption protections, potentially granting access to encrypted data. The recommended action is to upgrade to the patched versions: 10.0.10 for.NET 10.0, 9.0.18 for.NET 9.0, and 8.0.4 for.NET 8.0.
This incident is under investigation, and further details should be obtained from the primary sources. It is advised to consult the Microsoft Security Advisory CVE-2026-47304 for the most current information and guidance on mitigating this vulnerability.
How 0Day mitigates this
System.Security.Cryptography.Xml is anywhere in your dependency tree, the engineers who own the affected repositories get a push alert the moment it is flagged — no manual audit to remember to run.Read how this differs from waiting on a scanner to catch a known advisory, or see the exact, read-only access 0Day needs to do this for an organization.