Vulnerability identifier: #VU6475

Vulnerability risk: Low

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-0248

CWE-ID: CWE-295

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Microsoft .NET Framework
Server applications / Frameworks for developing and running applications

Vendor: Microsoft

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

The weakness exists due to improper validation of certificates by Microsoft .NET Framework (and .NET Core) components. A remote attacker can force the usage of invalid certificates for certain use by affected component, disregard the Enhanced Key Usage taggings and bypass security restrictions.

Successful exploitation of the vulnerability results in security bypass.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Microsoft .NET Framework: 2.0, 3.5, 3.5.1, 4.6, 4.5.2, 4.7, 4.6.2, 4.6.1

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External links
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2017-0248

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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.