CVE-2021-26423
.NET Core and Visual Studio Denial of Service Vulnerability
No known exploitation. EPSS puts it in the 90th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
.NET Core Elevation of Privilege Vulnerability
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
3.9% chance of exploitation activity in the next 30 days, which ranks it in the 90th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
7 events over 1824 days, from the signal feeds we watch.
- Patch availablerecord updated
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified
Affected products
- Microsoft.NETCore.App.Runtime.win-x86OSS Libraries
- Microsoft.NETCore.App.Runtime.win-x64OSS Libraries
- Microsoft.NETCore.App.Runtime.win-arm64OSS Libraries
- Microsoft.NETCore.App.Runtime.win-armOSS Libraries
- Microsoft.NETCore.App.Runtime.osx-x64OSS Libraries
- Microsoft.NETCore.App.Runtime.Mono.osx-x64OSS Libraries
- Microsoft.NETCore.App.Runtime.Mono.LLVM.osx-x64OSS Libraries
- Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-x64OSS Libraries
- .NET CoreOSS Libraries / generic-library
- Microsoft Visual Studio 2019DevTools & CI / ide-editor
- PowerShell CoreDevTools & CI / ide-editor
- Microsoft Visual Studio 2017DevTools & CI / ide-editor
- .NET 5.0Operating Systems / windows
- .NET Core 2.1OSS Libraries / generic-library
- .NET Core 3.1OSS Libraries / generic-library
- Microsoft Visual Studio 2017 version 15.9 (includes 15.0 - 15.8)DevTools & CI / ide-editor
And 27 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Scored 7.5 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity NoneNo integrity impact
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
Sources
References in the record
- github.com/dotnet/runtime/security/advisories/GHSA-rh58-r7jh-xhx3
- nvd.nist.gov/vuln/detail/CVE-2021-26423
- github.com/dotnet/announcements/issues/194
And 4 more references. See all after sign-in
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