How severe is CVE-2017-0256?

CVE-2017-0256 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2017-0256 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-0256?

CVE-2017-0256 primarily affects Microsoft Asp.net Model View Controller. In total, 101 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-0256?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2017-0256 published?

CVE-2017-0256 was published on 2017-05-12 and last updated on 2026-06-17.

CVE-2017-0256

CVE-2017-0256 is a medium-severity vulnerability in Microsoft Asp.net Model View Controller with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft Asp.net Model View Controller
Published: 2017-05-12
Last modified: 2026-06-17

Description

A spoofing vulnerability exists when the ASP.NET Core fails to properly sanitize web requests.

Frequently asked questions

What is CVE-2017-0256?: A spoofing vulnerability exists when the ASP.NET Core fails to properly sanitize web requests.
How severe is CVE-2017-0256?: CVE-2017-0256 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2017-0256 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-0256?: CVE-2017-0256 primarily affects Microsoft Asp.net Model View Controller. In total, 101 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-0256?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-0256 published?: CVE-2017-0256 was published on 2017-05-12 and last updated on 2026-06-17.

References

https://github.com/aspnet/Announcements/issues/239

Affected products (101)

cpe:2.3:a:microsoft:asp.net_model_view_controller:1.0.0:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_model_view_controller:1.0.1:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_model_view_controller:1.0.2:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_model_view_controller:1.0.3:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_model_view_controller:1.1.0:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_model_view_controller:1.1.1:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_model_view_controller:1.1.2:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.abstractions:1.0.0:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.abstractions:1.0.1:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.abstractions:1.0.2:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.abstractions:1.0.3:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.abstractions:1.1.0:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.abstractions:1.1.1:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.abstractions:1.1.2:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.apiexplorer:1.0.0:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.apiexplorer:1.0.1:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.apiexplorer:1.0.2:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.apiexplorer:1.0.3:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.apiexplorer:1.1.0:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.apiexplorer:1.1.1:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.apiexplorer:1.1.2:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.cors:1.0.0:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.cors:1.0.1:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.cors:1.0.2:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.cors:1.0.3:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.cors:1.1.0:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.cors:1.1.1:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.cors:1.1.2:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.dataannotations:1.0.0:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.dataannotations:1.0.1:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.dataannotations:1.0.2:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.dataannotations:1.0.3:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.dataannotations:1.1.0:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.dataannotations:1.1.1:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.dataannotations:1.1.2:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.formatters.json:1.0.0:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.formatters.json:1.0.1:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.formatters.json:1.0.2:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.formatters.json:1.0.3:*:*:*:*:asp.net:*:*
cpe:2.3:a:microsoft:microsoft.aspnetcore.mvc.formatters.json:1.1.0:*:*:*:*:asp.net:*:*

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