#.NET and Visual Studio

**What kind of security feature could be bypassed by successfully exploiting this vulnerability?** A security feature bypass vulnerability exists when Microsoft .NET Framework-based applications use X.509 chain building APIs but do not completely validate the X.509 certificate due to a logic flaw. An attacker could present an arbitrary untrusted certificate with malformed signatures, triggering a bug in the framework. The framework will correctly report that X.509 chain building failed, but it will return an incorrect reason code for the failure. Applications which utilize this reason code to make their own chain building trust decisions may inadvertently treat this scenario as a successful chain build. This could allow an adversary to subvert the app's typical authentication logic.

**According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?** Exploitation of this vulnerability requires that an attacker convinces a user to open a maliciously crafted package file in Visual Studio.

**According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?** Exploitation of this vulnerability requires that an attacker convinces a user to open a maliciously crafted package file in Visual Studio.

**According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?** Exploitation of this vulnerability requires that an attacker convinces a user to open a maliciously crafted package file in Visual Studio.

**According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?** Exploitation of this vulnerability requires that an attacker convinces a user to open a maliciously crafted package file in Visual Studio.

**According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?** Successful exploitation of this vulnerability requires an attacker to win a race condition and also to take additional actions prior to exploitation to prepare the target environment.

**According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?** Successful exploitation of this vulnerability requires an attacker to win a race condition and also to take additional actions prior to exploitation to prepare the target environment.

**According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?** An attacker must send the user a malicious file and convince them to open it.

**According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?** Exploitation of this vulnerability requires that a user trigger the payload in the application.

**According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?** Exploitation of this vulnerability requires that a user trigger the payload in the application.