CVE-2024-0057
dotnet: X509 Certificates - Validation Bypass across Azure
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · January 9, 2024
Updated · November 21, 2025
Description
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.
Statement
The ability for an attacker to exploit this vulnerability by presenting an arbitrary untrusted certificate with malformed signatures can lead to a breach in the application's authentication logic. This loophole poses a serious threat, as it could lead to unauthorized access, data breaches, and the compromise of sensitive information.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE-295 · Improper Certificate Validation