CVE-2017-0256 json
Moderate severity vulnerability that affects Microsoft.AspNetCore.Mvc
published 2017-05-12 9 y ago modified 2026-06-17 4 mo ago also GHSA-j8f4-2w4p-mhjc , EUVD-2018-0627
- cvss
- 5.3
- version 3.0, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 3.5%
- EPSS 3.5% chance of exploitation in 30 days, percentile 89%
- public exploits
- 0
- none known
Summary
A spoofing vulnerability exists when the ASP.NET Core fails to properly sanitize web requests.
Patch / fix
- nuget Microsoft.AspNetCore.Mvc 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.Core 1.0.4, 1.1.3
- nuget System.Net.Http 4.1.2, 4.3.2
- nuget System.Text.Encodings.Web 4.0.1, 4.3.1
- nuget System.Net.Http.WinHttpHandler 4.0.1, 4.3.1
- nuget System.Net.Security 4.0.1, 4.3.1
- nuget System.Net.WebSockets.Client 4.0.1, 4.3.1
- nuget Microsoft.AspNetCore.Mvc.Abstractions 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.ApiExplorer 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.Cors 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.DataAnnotations 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.Formatters.Json 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.Formatters.Xml 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.Localization 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.Razor.Host 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.Razor 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.TagHelpers 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.ViewFeatures 1.0.4, 1.1.3
- nuget Microsoft.AspNetCore.Mvc.WebApiCompatShim 1.0.4, 1.1.3
Exploit prediction
3.54% chance of exploitation in the next 30 days, higher than 89% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.0 | 5.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:P/A:N |
| GitHub | 3.0 | 5.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| nuget | Microsoft.AspNetCore.Mvc | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.Core | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | System.Net.Http | >=4.1.1, <4.1.2 >=4.3.1, <4.3.2 |
4.1.2 4.3.2 |
| nuget | System.Text.Encodings.Web | >=4.0.0, <4.0.1 >=4.3.0, <4.3.1 |
4.0.1 4.3.1 |
| nuget | System.Net.Http.WinHttpHandler | >=4.0.0, <4.0.1 >=4.3.0, <4.3.1 |
4.0.1 4.3.1 |
| nuget | System.Net.Security | >=4.0.0, <4.0.1 >=4.3.0, <4.3.1 |
4.0.1 4.3.1 |
| nuget | System.Net.WebSockets.Client | >=4.0.0, <4.0.1 >=4.3.0, <4.3.1 |
4.0.1 4.3.1 |
| nuget | Microsoft.AspNetCore.Mvc.Abstractions | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.ApiExplorer | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.Cors | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.DataAnnotations | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.Formatters.Json | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.Formatters.Xml | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.Localization | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.Razor.Host | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.Razor | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.TagHelpers | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.ViewFeatures | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
| nuget | Microsoft.AspNetCore.Mvc.WebApiCompatShim | >=1.0.0, <1.0.4 >=1.1.0, <1.1.3 |
1.0.4 1.1.3 |
Affected products
- Microsoft Corporation ASP.NET Core
Classification
- Weakness
-
- CWE-20 Improper Input Validation
References
-
github.com
/aspnet/Announcements/issues/239
web, technical-description, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2017-0256
advisory
-
github.com
/advisories/GHSA-j8f4-2w4p-mhjc
advisory
Sources
- CVE List CVE-2017-0256
- GitHub Advisory GHSA-j8f4-2w4p-mhjc
- NVD CVE-2017-0256
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.