How severe is CVE-2020-1161?

CVE-2020-1161 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 none, and availability high.

Is CVE-2020-1161 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-1161?

CVE-2020-1161 primarily affects Microsoft Asp.net Core. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-1161?

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-2020-1161 published?

CVE-2020-1161 was published on 2020-05-21 and last updated on 2026-06-17.

CVE-2020-1161

CVE-2020-1161 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.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Asp.net Core
Published: 2020-05-21
Last modified: 2026-06-17

Description

A denial of service vulnerability exists when ASP.NET Core improperly handles web requests, aka 'ASP.NET Core Denial of Service Vulnerability'.

Frequently asked questions

What is CVE-2020-1161?: A denial of service vulnerability exists when ASP.NET Core improperly handles web requests, aka 'ASP.NET Core Denial of Service Vulnerability'.
How severe is CVE-2020-1161?: CVE-2020-1161 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 none, and availability high.
Is CVE-2020-1161 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-1161?: CVE-2020-1161 primarily affects Microsoft Asp.net Core. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-1161?: 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-2020-1161 published?: CVE-2020-1161 was published on 2020-05-21 and last updated on 2026-06-17.

References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1161

Affected products (3)

cpe:2.3:a:microsoft:asp.net_core:3.1:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:visual_studio_2017:*:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:visual_studio_2019:*:*:*:*:*:*:*:*

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