#VU13769 Security restrictions bypass in Microsoft .NET Framework and ASP.NET Core MVC - CVE-2018-8356

Vulnerability identifier: #VU13769

Vulnerability risk: Low

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-8356

CWE-ID: CWE-264

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Microsoft .NET Framework
Server applications / Frameworks for developing and running applications
ASP.NET Core MVC
Universal components / Libraries / Software for developers

Vendor: Microsoft

Description

The vulnerability allows a remote attacker to bypass security restrictions on the target system.

The vulnerability exists due to  improper validation of certificates by .NET Framework components. A remote unauthenticated attacker can present expired certificates when challenged and bypass security restrictions to conduct further attacks.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Microsoft .NET Framework: 3.0, 3.5 - 3.5.1, 4.5.2, 4.6 - 4.6.2, 4.7 - 4.7.2

ASP.NET Core MVC: 1.0.0 - 2.0

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External links
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8356

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.