DotNetZip Replacement for .NET Framework 4.8

Problem Statement

DotNetZip, a long-standing ZIP archive library for .NET, has been officially deprecated and archived by its maintainers. For applications targeting .NET Framework 4.8, this creates two critical challenges:

1. Security vulnerability: The latest DotNetZip version (1.16.0) contains a critical vulnerability (CVE-2024-48510) with a 9.8 CVSS score
2. Maintenance risk: No future updates or security patches will be released
3. Minimal upgrade guidance: Unlike previous migrations (e.g., Ionic.Zip → DotNetZip), no official replacement path exists

Project maintainers must address these risks while minimizing code changes in large solutions (80+ projects in some cases).

Recommended Solutions

1. Maintained Forks (Minimal Code Changes)

The most straightforward migration path is using community-maintained forks:

ProDotNetZip

// NuGet: Install-Package ProDotNetZip
using ProDotNetZip;

// Existing DotNetZip code continues working
using (var zip = new ZipFile())
{
    zip.AddFile("document.txt");
    zip.Save("archive.zip");
}

• ✅ Fixes CVE-2024-48510 vulnerability
• ✅ .NET Standard 2.0 (compatible with .NET 4.8)
• ⚠️ New fork requires monitoring for long-term support

DotNetZip.Original

// NuGet: Install-Package DotNetZip.Original
using DotNetZip.Original;

// Identical API to original DotNetZip
var zip = ZipFile.Read("archive.zip");
zip.ExtractAll(@"C:\unpacked");

• ✅ Maintains original DotNetZip API surface
• ✅ .NET Standard 2.0 compatible
• 🔍 Verify specific vulnerability fixes

Migration Steps for Forks

1. Remove deprecated DotNetZip NuGet package
2. Install replacement fork (ProDotNetZip or DotNetZip.Original)
3. Update namespaces (ProDotNetZip instead of DotNetZip)
4. Rebuild solution - Minimal runtime changes typically required

2. Built-in System.IO.Compression (For Basic Use Cases)

For applications not requiring encryption or advanced features:

using System.IO.Compression;

// Create a ZIP archive
ZipFile.CreateFromDirectory(sourceFolder, destinationArchive);

// Extract ZIP archive
ZipFile.ExtractToDirectory(sourceArchive, destinationFolder);

Limitations:

• ❌ No encryption/password support
• ❌ Limited compression control
• ❌ Different API requires code rewrites

3. Commercial Solutions (Enterprise Needs)

When using commercial component libraries:

// Example wrapper interface for commercial zip library
public interface IZipOperations
{
    void CreateArchive(string outputPath, IEnumerable<string> files);
    void ExtractToDirectory(string archivePath, string destination);
}

// Implement using commercial SDK
public class VendorZipService : IZipOperations
{
    public void CreateArchive(string outputPath, IEnumerable<string> files)
    {
        // Map to commercial SDK's method
        ThirdPartyZip.Create(outputPath).AddFiles(files);
    }
}

Implementation workflow:

1. Identify compression features used
2. Create adapter interface matching DotNetZip methods
3. Implement using commercial SDK
4. Replace concrete DotNetZip calls with interface

Security First

Always verify security compliance for new dependencies. Check NVD for vulnerability reports before adopting any zip library.

Alternative Options Comparison

Solution	Migration Effort	Security	Encryption	Long-Term Viability
ProDotNetZip	Low ⭐️	✅ Patched	✅	Medium
DotNetZip.Original	Low ⭐️	❓ Unknown	✅	Medium
System.IO.Compression	High ⭐⭐⭐	✅ Official	❌	High
Commercial Wrapper	Medium ⭐⭐	Varies ✅⚠️	Varies	High
SharpZipLib	Moderate ⭐⭐	⚠️ Unmaintained	✅	Low

Migration Strategy Guide

1. Audit usage:

   # Find all DotNetZip references in solution
   Get-ChildItem -Recurse -Filter *.cs | Select-String "Ionic.Zip|DotNetZip"

2. Evaluate feature requirements:

   • Password protection?
   • Special compression methods?
   • Progress reporting?

3. Choose replacement path:

4. Refactor incrementally:

   • Wrap zip functionality behind interfaces
   • Implement replacement in phases
   • Use adapter pattern to minimize changes

Critical Action

Remove DotNetZip immediately if using vulnerable versions (≤ 1.16.0). The CVE-2024-48510 vulnerability allows arbitrary code execution.

Long-Term Recommendations

For .NET Framework 4.8 applications:

1. Use ProDotNetZip for minimal disruption
2. Validate vulnerability fixes in your specific environment
3. Monitor fork activity (github issues, releases)
4. For new development consider:
   • .NET's built-in compression APIs
   • Well-maintained commercial libraries

The community-driven forks represent the most seamless transition for existing DotNetZip users, though all solutions should include security scanning in your SDLC.