CVE-2017-0247 — Vulnerability in Microsoft.AspNetCore.Mvc — CVE...

HIGH

ASP.NET Core fails to properly validate web requests

Published October 16, 2018Updated November 8, 2023Source: osv

Summary

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.

Advisory Timeline

First published October 16, 2018 (2918 days ago).
Last revised November 8, 2023 — 1848 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

NuGet

Update Microsoft.AspNetCore.Mvc to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.Localization to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.Localization --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.Razor to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.Razor --version 1.0.4

NuGet

Update System.Net.Http to 4.1.2 or later

dotnet add package System.Net.Http --version 4.1.2

NuGet

Update System.Text.Encodings.Web to 4.0.1 or later

dotnet add package System.Text.Encodings.Web --version 4.0.1

NuGet

Update Microsoft.AspNetCore.Mvc.Formatters.Json to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.Formatters.Json --version 1.0.4

NuGet

Update Microsoft.AspNetCore.Mvc.WebApiCompatShim to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.WebApiCompatShim --version 1.1.3

NuGet

Update System.Net.WebSockets.Client to 4.3.1 or later

dotnet add package System.Net.WebSockets.Client --version 4.3.1

NuGet

Update Microsoft.AspNetCore.Mvc.ApiExplorer to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.ApiExplorer --version 1.1.3

NuGet

Update System.Net.Security to 4.3.1 or later

dotnet add package System.Net.Security --version 4.3.1

NuGet

Update System.Net.WebSockets.Client to 4.0.1 or later

dotnet add package System.Net.WebSockets.Client --version 4.0.1

NuGet

Update Microsoft.AspNetCore.Mvc.TagHelpers to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.TagHelpers --version 1.0.4

NuGet

Update System.Net.Http.WinHttpHandler to 4.5.4 or later

dotnet add package System.Net.Http.WinHttpHandler --version 4.5.4

NuGet

Update Microsoft.AspNetCore.Mvc.Formatters.Json to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.Formatters.Json --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.Abstractions to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.Abstractions --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.Formatters.Xml to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.Formatters.Xml --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.Razor.Host to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.Razor.Host --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.Razor to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.Razor --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.Localization to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.Localization --version 1.0.4

NuGet

Update Microsoft.AspNetCore.Mvc.ViewFeatures to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.ViewFeatures --version 1.1.3

NuGet

Update System.Net.Http.WinHttpHandler to 4.0.1 or later

dotnet add package System.Net.Http.WinHttpHandler --version 4.0.1

NuGet

Update Microsoft.AspNetCore.Mvc.DataAnnotations to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.DataAnnotations --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.Core to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.Core --version 1.0.4

NuGet

Update Microsoft.AspNetCore.Mvc.TagHelpers to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.TagHelpers --version 1.1.3

NuGet

Update System.Text.Encodings.Web to 4.3.1 or later

dotnet add package System.Text.Encodings.Web --version 4.3.1

NuGet

Update Microsoft.AspNetCore.Mvc.Razor.Host to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.Razor.Host --version 1.0.4

NuGet

Update Microsoft.AspNetCore.Mvc.Core to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.Core --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.ViewFeatures to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.ViewFeatures --version 1.0.4

NuGet

Update Microsoft.AspNetCore.Mvc to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc --version 1.0.4

NuGet

Update Microsoft.AspNetCore.Mvc.Cors to 1.1.3 or later

dotnet add package Microsoft.AspNetCore.Mvc.Cors --version 1.1.3

NuGet

Update Microsoft.AspNetCore.Mvc.Cors to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.Cors --version 1.0.4

NuGet

Update System.Net.Http to 4.3.2 or later

dotnet add package System.Net.Http --version 4.3.2

NuGet

Update Microsoft.AspNetCore.Mvc.Formatters.Xml to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.Formatters.Xml --version 1.0.4

NuGet

Update Microsoft.AspNetCore.Mvc.Abstractions to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.Abstractions --version 1.0.4

NuGet

Update Microsoft.AspNetCore.Mvc.WebApiCompatShim to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.WebApiCompatShim --version 1.0.4

NuGet

Update System.Net.Security to 4.0.1 or later

dotnet add package System.Net.Security --version 4.0.1

NuGet

Update Microsoft.AspNetCore.Mvc.DataAnnotations to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.DataAnnotations --version 1.0.4

NuGet

Update Microsoft.AspNetCore.Mvc.ApiExplorer to 1.0.4 or later

dotnet add package Microsoft.AspNetCore.Mvc.ApiExplorer --version 1.0.4

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (38)

Affects 1 ecosystem: nuget (19).

Package	Ecosystem	Affected	Fixed In
Microsoft.AspNetCore.Mvc	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.Localization	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.Razor	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
System.Net.Http	nuget	4.1.1	4.1.2
System.Text.Encodings.Web	nuget	4.0.0	4.0.1
Microsoft.AspNetCore.Mvc.Formatters.Json	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
Microsoft.AspNetCore.Mvc.WebApiCompatShim	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
System.Net.WebSockets.Client	nuget	4.3.0	4.3.1
Microsoft.AspNetCore.Mvc.ApiExplorer	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
System.Net.Security	nuget	4.3.0	4.3.1
System.Net.WebSockets.Client	nuget	4.0.0	4.0.1
Microsoft.AspNetCore.Mvc.TagHelpers	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
System.Net.Http.WinHttpHandler	nuget	4.3.0, 4.3.1, 4.3.2, 4.3.3 (+11 more)	4.5.4
Microsoft.AspNetCore.Mvc.Formatters.Json	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.Abstractions	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.Formatters.Xml	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.Razor.Host	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.Razor	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.Localization	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
Microsoft.AspNetCore.Mvc.ViewFeatures	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
System.Net.Http.WinHttpHandler	nuget	4.0.0	4.0.1
Microsoft.AspNetCore.Mvc.DataAnnotations	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.Core	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
Microsoft.AspNetCore.Mvc.TagHelpers	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
System.Text.Encodings.Web	nuget	4.3.0	4.3.1
Microsoft.AspNetCore.Mvc.Razor.Host	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
Microsoft.AspNetCore.Mvc.Core	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.ViewFeatures	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
Microsoft.AspNetCore.Mvc	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
Microsoft.AspNetCore.Mvc.Cors	nuget	1.1.0, 1.1.1, 1.1.2	1.1.3
Microsoft.AspNetCore.Mvc.Cors	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
System.Net.Http	nuget	4.3.1	4.3.2
Microsoft.AspNetCore.Mvc.Formatters.Xml	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
Microsoft.AspNetCore.Mvc.Abstractions	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
Microsoft.AspNetCore.Mvc.WebApiCompatShim	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
System.Net.Security	nuget	4.0.0	4.0.1
Microsoft.AspNetCore.Mvc.DataAnnotations	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4
Microsoft.AspNetCore.Mvc.ApiExplorer	nuget	1.0.0, 1.0.1, 1.0.2, 1.0.3	1.0.4

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CWE-20
Improper Input ValidationMITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 7.5 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

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

References

Frequently Asked Questions

What is CVE-2017-0247?: ASP.NET Core fails to properly validate web requests This vulnerability has been assigned a severity rating of HIGH (CVSS score: 7.5/10).
How do I check if my project is affected by CVE-2017-0247?: CVE-2017-0247 affects Microsoft.AspNetCore.Mvc, Microsoft.AspNetCore.Mvc.Localization and Microsoft.AspNetCore.Mvc.Razor (and 16 more). Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2017-0247 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

7.5

High exploitability or significant impact. Prioritize remediation within days.

Also Known As

GHSA-6xh7-4v2w-36q6

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