CVE-2022-29145
📋 TL;DR
CVE-2022-29145 is a denial of service vulnerability in .NET and Visual Studio that allows attackers to crash affected applications by sending specially crafted requests. This affects systems running vulnerable versions of .NET Core, .NET 5, .NET 6, and Visual Studio. The vulnerability can be exploited remotely without authentication.
💻 Affected Systems
- .NET Core
- .NET 5
- .NET 6
- Visual Studio
📦 What is this software?
.net by Microsoft
.net by Microsoft
.net Core by Microsoft
Fedora by Fedoraproject
Fedora by Fedoraproject
Fedora by Fedoraproject
⚠️ Risk & Real-World Impact
Worst Case
Complete service disruption of affected .NET applications, potentially affecting multiple services simultaneously if they share vulnerable components.
Likely Case
Application crashes leading to service downtime, requiring manual restart of affected services.
If Mitigated
Minimal impact with proper network segmentation and updated systems; isolated crashes that don't affect overall service availability.
🎯 Exploit Status
Microsoft has confirmed the vulnerability is remotely exploitable without authentication. While no public PoC exists, the low complexity suggests weaponization is likely.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: .NET 6.0.5, .NET 5.0.17, .NET Core 3.1.25; Visual Studio 2022 version 17.2
Vendor Advisory: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2022-29145
Restart Required: Yes
Instructions:
1. Update .NET runtime to patched versions via Windows Update or package manager. 2. Update Visual Studio 2022 to version 17.2 or later via Visual Studio Installer. 3. Restart affected applications and services after patching.
🔧 Temporary Workarounds
Network Segmentation
allRestrict network access to affected .NET applications to trusted sources only
Application Firewall Rules
allImplement rate limiting and request filtering at the network perimeter
🧯 If You Can't Patch
- Implement strict network access controls to limit exposure to trusted networks only
- Deploy web application firewalls with DoS protection and monitor for abnormal request patterns
🔍 How to Verify
Check if Vulnerable:
Check installed .NET versions: 'dotnet --info' on Linux/macOS or 'Get-ChildItem "HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP" -Recurse | Get-ItemProperty -Name Version,Release -ErrorAction 0 | Where {$_.PSChildName -match "^(?!S)\p{L}"} | Select PSChildName, Version, Release' on WindowsCheck Version:
dotnet --version (for .NET) or devenv.exe /? (for Visual Studio)Verify Fix Applied:
Verify installed version is equal to or higher than: .NET 6.0.5, .NET 5.0.17, .NET Core 3.1.25, or Visual Studio 2022 17.2📡 Detection & Monitoring
Log Indicators:
- Unexpected application crashes
- High memory consumption followed by service termination
- Error logs containing stack traces from .NET runtime
Network Indicators:
- Unusual traffic patterns to .NET application endpoints
- Multiple connection attempts from single sources
SIEM Query:
EventID: 1000 OR EventID: 1001 OR (source: "Application Error" AND process_name: "dotnet.exe" OR "devenv.exe")🔗 References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2022-29145
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GNXQL7EZORGU4PZCPJ5EPQ4P7IEY3ZZO/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IBYSBUDJYQ76HK4TULXVIIPCKK2U6WDB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W5FPEQ6BTYRGTS6IYCDTZW6YF5HLQ3BY/
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2022-29145
