How severe is CVE-2018-8171?

CVE-2018-8171 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2018-8171 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-8171?

CVE-2018-8171 primarily affects Microsoft Asp.net Core. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-8171?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-8171 published?

CVE-2018-8171 was published on 2018-07-11 and last updated on 2026-06-17.

CVE-2018-8171

CVE-2018-8171 is a high-severity vulnerability in Microsoft Asp.net Core with a CVSS 3.x base score of 7.5. 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-287.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 10% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Microsoft Asp.net Core
Published: 2018-07-11
Last modified: 2026-06-17

Description

A Security Feature Bypass vulnerability exists in ASP.NET when the number of incorrect login attempts is not validated, aka "ASP.NET Security Feature Bypass Vulnerability." This affects ASP.NET, ASP.NET Core 1.1, ASP.NET Core 1.0, ASP.NET Core 2.0, ASP.NET MVC 5.2.

Frequently asked questions

What is CVE-2018-8171?: A Security Feature Bypass vulnerability exists in ASP.NET when the number of incorrect login attempts is not validated, aka "ASP.NET Security Feature Bypass Vulnerability." This affects ASP.NET, ASP.NET Core 1.1, ASP.NET Core 1.0, ASP.NET Core 2.0, ASP.NET MVC 5.2.
How severe is CVE-2018-8171?: CVE-2018-8171 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2018-8171 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-8171?: CVE-2018-8171 primarily affects Microsoft Asp.net Core. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-8171?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-8171 published?: CVE-2018-8171 was published on 2018-07-11 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:microsoft:asp.net_core:1.0:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_core:1.1:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_core:2.0:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_model_view_controller:5.2:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:asp.net_webpages:3.2.3:*:*:*:*:*:*:*

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