CVE-2021-26423
.NET Core and Visual Studio Denial of Service Vulnerability
HIGH
7.5
CVSS Score
Published: August 12, 2021 at 06:11 PM UTC
Updated: August 10, 2026 at 04:17 PM UTC
5 products affected across 1 vendor.netVisual Studio 2019Visual Studio 2017
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Severity
HIGH7.5
Exploit prediction
EPSS 4%
SSVC
No known exploit
Description
.NET Core and Visual Studio Denial of Service Vulnerability
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Affected range stops below 5.0.9, so it looks safe — our inference, not a vendor statement
Affected range stops below 2.1.30, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.1.18, so it looks safe — our inference, not a vendor statement
Affected range stops below 7.0.7, so it looks safe — our inference, not a vendor statement
Affected range stops below 7.1.4, so it looks safe — our inference, not a vendor statement
Affected range stops below 15.9.38, so it looks safe — our inference, not a vendor statement
15.0.0 ≤ v < 16.9.1016.0 ≤ v ≤ 16.1016.0 ≤ v < 16.4.2516.0.0 ≤ v < 16.7.1816.10.0 ≤ v < 16.10.58.1.0 ≤ v < 8.10.715.0.016.016.0.016.10.08.1.08.10
Affected range stops below 16.10.5, so it looks safe — our inference, not a vendor statement
Affected range stops below 16.4.25, so it looks safe — our inference, not a vendor statement
Affected range stops below 16.7.18, so it looks safe — our inference, not a vendor statement
Affected range stops below 16.9.10, so it looks safe — our inference, not a vendor statement
Affected range stops below 8.10.7, 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:
References (2)
PatchVendor Advisory
Source: [email protected]
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26423Vendor AdvisoryPatch
Source: cverecord
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26423SSVC — Action Prioritization
SSVCNo known exploitAutomatablePartial impact
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
7.5HIGHmicrosoft
Vector?
Quick Info
StatusMODIFIED
CWE
NVD-CWE-noinfo
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