#VU17638 Spoofing attack in Microsoft products - CVE-2019-0657

Vulnerability identifier: #VU17638

Vulnerability risk: Low

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

CVE-ID: CVE-2019-0657

CWE-ID: CWE-451

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
Visual Studio
Universal components / Libraries / Software for developers

Vendor: Microsoft

Description

The vulnerability allows a remote attacker to conduct spoofing attack.

The vulnerability exists in thev .Net Framework API's and Visual Studio in the way they parse URL's. A remote attacker can provide a URL string to an application that attempts to verify that the URL belongs to a specific hostname or to a subdomain of that hostname, bypass security logic intended to ensure that a user-provided URL belonged to a specific hostname or a subdomain of that hostname to cause privileged communication to be made to an untrusted service as if it was a trusted service.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Microsoft .NET Framework: 2.0, 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 - 2.2

Visual Studio: 15.0 26228.04, 15.9

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External links
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0657

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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.