CVE-2017-0247

Public Exploit

Description

A denial of service vulnerability exists when the ASP.NET Core fails to properly validate web requests. NOTE: Microsoft has not commented on third-party claims that the issue is that the TextEncoder.EncodeCore function in the System.Text.Encodings.Web package in ASP.NET Core Mvc before 1.0.4 and 1.1.x before 1.1.3 allows remote attackers to cause a denial of service by leveraging failure to properly calculate the length of 4-byte characters in the Unicode Non-Character range.

Category

7.5
CVSS
Severity: High
CVSS 3.0 •
CVSS 2.0 •
EPSS 11.12% Top 10%
Vendor Advisory microsoft.com
Affected: Microsoft Corporation ASP.NET Core
Published at:
Updated at:

References

Link Tags
https://technet.microsoft.com/en-us/library/security/4021279.aspx patch vendor advisory
https://github.com/aspnet/Announcements/issues/239 third party advisory technical description
https://www.sidertia.com/Home/Community/Blog/2017/05/18/ASPNET-Core-Unicode-Non-Char-Encoding-DoS third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2017-0247?
CVE-2017-0247 has been scored as a high severity vulnerability.
How to fix CVE-2017-0247?
To fix CVE-2017-0247, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2017-0247 being actively exploited in the wild?
It is possible that CVE-2017-0247 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~11% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2017-0247?
CVE-2017-0247 affects Microsoft Corporation ASP.NET Core.
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