CVE-2021-31957
ASP.NET Core Denial of Service Vulnerability
MEDIUM
5.9
CVSS Score
Published: June 8, 2021 at 10:46 PM UTC
Updated: October 7, 2026 at 05:16 PM UTC
4 products affected across 2 vendorsFedora.netVisual Studio 2019
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Severity
MEDIUM5.9
Exploit prediction
EPSS 5%
SSVC
No known exploit
Description
ASP.NET Core Denial of Service Vulnerability
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Affected range stops below 5.0.7, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.1.16, so it looks safe — our inference, not a vendor statement
15.0.0 ≤ v < 16.9.716.0 ≤ v ≤ 16.1016.0 ≤ v < 16.4.2316.0.0 ≤ v < 16.7.1616.10.0 ≤ v < 16.10.18.1.0 ≤ v < 8.10.1*15.0.016.016.0.016.10.016.98.1.08.10
Affected range stops below 16.10.1, so it looks safe — our inference, not a vendor statement
Affected range stops below 16.4.23, so it looks safe — our inference, not a vendor statement
Affected range stops below 16.7.16, so it looks safe — our inference, not a vendor statement
Affected range stops below 16.9.7, so it looks safe — our inference, not a vendor statement
Affected range stops below 8.10.1, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4PRVVLXXQEF4SEJOBV3VRJHGX7YHY2CG/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVCDYIP4A6DDRT7G6P3ZW6PKNK2DNWJ2/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PMHWHRRYDHKM6BIINW5V7OCSW4SDWB4W/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VMAO4NG2OQ4PCXUQWMNSCMYWLIJJY6UY/
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31957
References (5)
Vendor Advisoryx_refsource_FEDORA
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4PRVVLXXQEF4SEJOBV3VRJHGX7YHY2CG/Vendor Advisoryx_refsource_FEDORA
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVCDYIP4A6DDRT7G6P3ZW6PKNK2DNWJ2/Vendor Advisoryx_refsource_FEDORA
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PMHWHRRYDHKM6BIINW5V7OCSW4SDWB4W/Vendor Advisoryx_refsource_FEDORA
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VMAO4NG2OQ4PCXUQWMNSCMYWLIJJY6UY/x_refsource_MISCPatchVendor Advisory
Source: [email protected]
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31957SSVC — Action Prioritization
SSVCNo known exploitNot automatablePartial impact
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
5.9MEDIUMmicrosoft
Vector?
Quick Info
StatusMODIFIED
CWE
NVD-CWE-noinfoCWE-400
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