CVE-2022-23267 — Microsoft.AspNetCore.App.…
HIGHCVE-2022-23267 is a high-severity (CVSS 7.5) vulnerability in Microsoft.AspNetCore.App.Runtime.linux-arm. A fix is available for Microsoft.AspNetCore.App.Runtime.linux-arm — see the affected versions and patch details below.
.NET Denial of Service Vulnerability
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2022-23267.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2022-23267 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
Microsoft.AspNetCore.App.Runtime.linux-arm.NETMicrosoft.AspNetCore.App.Runtime.linux-arm64.NETMicrosoft.AspNetCore.App.Runtime.linux-musl-arm64.NETMicrosoft.AspNetCore.App.Runtime.linux-musl-x64.NETMicrosoft.AspNetCore.App.Runtime.linux-x64.NETMicrosoft.AspNetCore.App.Runtime.osx-x64.NETMicrosoft.AspNetCore.App.Runtime.win-arm.NETMicrosoft.AspNetCore.App.Runtime.win-arm64+25 moreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.
Description
Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 6.0, .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.
A vulnerability exists in .NET 6.0, .NET 5.0 and .NET Core 3.1 where a malicious client can cause a Denial of Service via excess memory allocations through HttpClient.
Affected software
- Any .NET 6.0 application running on .NET 6.0.4 or earlier.
- Any .NET 5.0 application running .NET 5.0.16 or earlier.
- Any .NET Core 3.1 applicaiton running on .NET Core 3.1.24 or earlier.
Patches
-
If you're using .NET Core 6.0, you should download and install Runtime 6.0.5 or SDK 6.0.105 (for Visual Studio 2022 v17.0) or SDK 6.0.203 (for Visual Studio 2022 v17.1) from https://dotnet.microsoft.com/download/dotnet-core/6.0.
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If you're using .NET 5.0, you should download and install Runtime 5.0.17 or SDK 5.0.214 (for Visual Studio 2019 v16.9) or SDK 5.0.408 (for Visual Studio 2011 v16.11) from https://dotnet.microsoft.com/download/dotnet-core/5.0.
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If you're using .NET Core 3.1, you should download and install Runtime 3.1.25 or SDK 3.1.419 (for Visual Studio 2019 v16.9 or Visual Studio 2011 16.11 or Visual Studio 2022 17.0 or Visual Studio 2022 17.1 ) from https://dotnet.microsoft.com/download/dotnet-core/3.1.
.NET 6.0, .NET 5.0 and .NET Core 3.1 updates are also available from Microsoft Update. To access this either type "Check for updates" in your Windows search, or open Settings, choose Update & Security and then click Check for Updates.
Other Details
Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/221 An Issue for this can be found at https://github.com/dotnet/runtime/issues/69149 MSRC details for this can be found at https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2022-23267
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | Microsoft.AspNetCore.App.Runtime.linux-arm | ≥ 3.0.0&&< 3.1.25 | 3.1.25dotnet add package Microsoft.AspNetCore.App.Runtime.linux-arm --version 3.1.25 |
| .NETNuGet | Microsoft.AspNetCore.App.Runtime.linux-arm64 | ≥ 3.0.0&&< 3.1.25 | 3.1.25dotnet add package Microsoft.AspNetCore.App.Runtime.linux-arm64 --version 3.1.25 |
| .NETNuGet | Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 | ≥ 3.0.0&&< 3.1.25 | 3.1.25dotnet add package Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 --version 3.1.25 |
| .NETNuGet | Microsoft.AspNetCore.App.Runtime.linux-musl-x64 | ≥ 3.0.0&&< 3.1.25 | 3.1.25dotnet add package Microsoft.AspNetCore.App.Runtime.linux-musl-x64 --version 3.1.25 |
| .NETNuGet | Microsoft.AspNetCore.App.Runtime.linux-x64 | ≥ 3.0.0&&< 3.1.25 | 3.1.25dotnet add package Microsoft.AspNetCore.App.Runtime.linux-x64 --version 3.1.25 |
| .NETNuGet | Microsoft.AspNetCore.App.Runtime.osx-x64 | ≥ 3.0.0&&< 3.1.25 | 3.1.25dotnet add package Microsoft.AspNetCore.App.Runtime.osx-x64 --version 3.1.25 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Microsoft.AspNetCore.App.Runtime.linux-arm, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Microsoft.AspNetCore.App.Runtime.linux-arm to 3.1.25 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-23267 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2022-23267 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2022-23267. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Affected .NET versions: 6.0, 5.0, 3.1
| Product | Fixed in | Advisory |
|---|---|---|
| .NET Core on Red Hat Enterprise Linux | rh-dotnet31-dotnet-0:3.1.419-1.el7_9 | RHSA-2022:2194 |
| .NET Core on Red Hat Enterprise Linux | rh-dotnet50-dotnet-0:5.0.214-1.el7_9 | RHSA-2022:2196 |
| .NET Core on Red Hat Enterprise Linux | rh-dotnet60-dotnet-0:6.0.105-1.el7_9 | RHSA-2022:2195 |
| Red Hat Enterprise Linux 8 | dotnet6.0-0:6.0.105-1.el8_6 | RHSA-2022:2199 |
| Red Hat Enterprise Linux 8 | dotnet5.0-0:5.0.214-1.el8_6 | RHSA-2022:2200 |
| Red Hat Enterprise Linux 8 | dotnet3.1-0:3.1.419-1.el8_6 | RHSA-2022:2202 |
| Red Hat Enterprise Linux 9 | dotnet6.0-0:6.0.105-1.el9_0 | RHSA-2022:4588 |
Frequently Asked Questions
Is CVE-2022-23267 in your dependencies?
O3 Security finds CVE-2022-23267 across NuGet dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.