CVE-2021-26423: Microsoft.NETCore.App.Runtime.win arm .NET Core Elevation Of Privilege Vulnerability
HIGHCVE-2021-26423 is a HIGH (CVSS 7.5) .net core elevation of privilege vulnerability (General Security Weakness) affecting Microsoft.NETCore.App.Runtime.win arm libraries in the NuGet ecosystem. The issue involves .net core elevation of privilege vulnerability. Remediation is available by upgrading affected packages to version 3.1.18, 5.0.9.
CVE-2021-26423 at a Glance
Security Impact
CVSS: 7.5
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
How to Fix CVE-2021-26423
To remediate this vulnerability, upgrade all affected Microsoft.NETCore.App.Runtime.win arm dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade Microsoft.NETCore.App.Runtime.win-arm to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.win-x86 to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.win-x86 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.win-x64 to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.win-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.win-arm64 to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.win-arm64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.win-arm to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.osx-x64 to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.osx-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.osx-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.LLVM.osx-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-arm64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.osx-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-arm64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.linux-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.linux-musl-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.linux-arm64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.Mono.linux-arm to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.linux-x64 to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.linux-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.linux-musl-x64 to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.linux-musl-x64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.linux-musl-arm64 to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.linux-musl-arm64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.linux-musl-arm to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.rhel.6-x64 to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.linux-arm64 to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.linux-arm64 to 5.0.9
Upgrade Microsoft.NETCore.App.Runtime.linux-arm to 3.1.18
Upgrade Microsoft.NETCore.App.Runtime.linux-arm to 5.0.9
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for Microsoft.NETCore.App.Runtime.win-arm
How to Check if You Are Affected
To determine whether your application is affected by CVE-2021-26423, inspect your project dependencies for Microsoft.NETCore.App.Runtime.win arm:
inspect dependencies for Microsoft.NETCore.App.Runtime.win-arm
Analyze the terminal output to locate any version of Microsoft.NETCore.App.Runtime.win arm in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.1.18), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under General Security Weakness. In Microsoft.NETCore.App.Runtime.win arm, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2021-26423 Affected Microsoft.NETCore.App.Runtime.win arm Versions
33 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
Microsoft.NETCore.App.Runtime.win-arm
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.win-x86
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.win-x86
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.win-x64
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.win-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.win-arm64
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.win-arm64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.win-arm
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.osx-x64
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.osx-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.osx-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.LLVM.osx-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-arm64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.osx-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-arm64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.linux-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.linux-musl-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.linux-arm64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.Mono.linux-arm
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.linux-x64
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.linux-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.linux-musl-x64
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.linux-musl-x64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.linux-musl-arm64
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.linux-musl-arm64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.linux-musl-arm
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.rhel.6-x64
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.linux-arm64
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.linux-arm64
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
|
Microsoft.NETCore.App.Runtime.linux-arm
|
NuGet |
≥ 3.1.0
< 3.1.18
|
3.1.18
|
|
Microsoft.NETCore.App.Runtime.linux-arm
|
NuGet |
≥ 5.0.0
< 5.0.9
|
5.0.9
|
References
Frequently Asked Questions
What is CVE-2021-26423?
Which Microsoft.NETCore.App.Runtime.win arm versions are affected?
What version fixes CVE-2021-26423?
Is Microsoft.NETCore.App.Runtime.win-arm affected?
Is Microsoft.NETCore.App.Runtime.win-x86 affected?
What is the CVSS score of CVE-2021-26423?
What CWE is associated with CVE-2021-26423?
How can I check NuGet dependencies for CVE-2021-26423?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-rh58-r7jh-xhx3",
"modified" : "2022-10-25T17:33:12Z",
"published" : "2022-10-25T17:33:12Z",
"aliases" : [ "CVE-2021-26423" ],
"summary" : ".NET Core Elevation of Privilege Vulnerability",
"details" : "Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 5.0 and .NET Core 3.1. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nA denial of service vulnerability exists in .NET 5.0, .NET Core 3.1 and .NET Core 2.1 where .NET (Core) server applications providing WebSocket endpoints could be tricked into endlessly looping while trying to read a single WebSocket frame. \n\n### Patches\n\n* If you're using .NET 5.0, you should download and install Runtime 5.0.9 or SDK 5.0.206 (for Visual Studio 2019 v16.8) or SDK 5.0.303 (for Visual Studio 2019 V16.10) from https://dotnet.microsoft.com/download/dotnet-core/5.0.\n\n* If you're using .NET Core 3.1, you should download and install Runtime 3.1.18 or SDK 3.1.118 (for Visual Studio 2019 v16.4) or 3.1.412 (for Visual Studio 2019 v16.7 or later) from https://dotnet.microsoft.com/download/dotnet-core/3.1.\n\n* If you're using .NET Core 2.1, you should download and install Runtime 2.1.29 or SDK 2.1.525 (for Visual Studio 2019 v15.9) or 2.1.817 from https://dotnet.microsoft.com/download/dotnet-core/2.1.\n\n\n#### Other Details\n\n- Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/194\n- An Issue for this can be found at https://github.com/dotnet/runtime/issues/57175\n- MSRC details for this can be found at https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-26423\n",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.win-x86"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.win-x86"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.win-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.win-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.win-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.win-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
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} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.win-arm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.win-arm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.osx-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.osx-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.osx-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.LLVM.osx-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.LLVM.linux-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.osx-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
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} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.LLVM.AOT.linux-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
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} ]
}, {
"package" : {
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"name" : "Microsoft.NETCore.App.Runtime.Mono.linux-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
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"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.linux-musl-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.linux-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.Mono.linux-arm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
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} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-musl-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-musl-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-musl-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-musl-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-musl-arm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.rhel.6-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-arm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.18"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NETCore.App.Runtime.linux-arm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.0.0"
}, {
"fixed" : "5.0.9"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/dotnet/runtime/security/advisories/GHSA-rh58-r7jh-xhx3"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-26423"
}, {
"type" : "WEB",
"url" : "https://github.com/dotnet/announcements/issues/194"
}, {
"type" : "WEB",
"url" : "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26423"
} ],
"database_specific" : {
"cwe_ids" : [ ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2022-10-25T17:33:12Z",
"nvd_published_at" : "2021-08-12T18:15:00Z"
}
}