CVE-2017-0247

HighCVSS 7.5/10Last modified Jun 17, 2026

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.

Metrics

CVSS 3.0 7.5/10CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Weakness enumeration

CWE-20

Affected software

Vendor	Product	Versions
Microsoft Corporation	ASP.NET Core	ASP.NET Core

References

https://github.com/aspnet/Announcements/issues/239Technical Description, Third Party Advisory
https://technet.microsoft.com/en-us/library/security/4021279.aspxPatch, Vendor Advisory
https://www.sidertia.com/Home/Community/Blog/2017/05/18/ASPNET-Core-Unicode-Non-Char-Encoding-DoSExploit, Third Party Advisory
https://github.com/aspnet/Announcements/issues/239Technical Description, Third Party Advisory
https://technet.microsoft.com/en-us/library/security/4021279.aspxPatch, Vendor Advisory
https://www.sidertia.com/Home/Community/Blog/2017/05/18/ASPNET-Core-Unicode-Non-Char-Encoding-DoSExploit, Third Party Advisory

Timeline

Published: May 12, 2017
Last modified: Jun 17, 2026
NVD status: Modified

Related CVEs from 2017

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