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Code Analyzer based on Omnisharp
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Successful Zip Bomb attacks occur when an application expands untrusted archive files without controlling the size of the expanded data, which can
lead to denial of service. A Zip bomb is usually a malicious archive file of a few kilobytes of compressed data but turned into gigabytes of
uncompressed data. To achieve this extreme compression ratio, attackers will
compress irrelevant data (eg: a long string of repeated bytes).
Ask Yourself Whether
Archives to expand are untrusted and:

   There is no validation of the number of entries in the archive. 
   There is no validation of the total size of the uncompressed data. 
   There is no validation of the ratio between the compressed and uncompressed archive entry. 

There is a risk if you answered yes to any of those questions.
Recommended Secure Coding Practices

   Define and control the ratio between compressed and uncompressed data, in general the data compression ratio for most of the legit archives is
  1 to 3. 
   Define and control the threshold for maximum total size of the uncompressed data. 
   Count the number of file entries extracted from the archive and abort the extraction if their number is greater than a predefined threshold, in
  particular it’s not recommended to recursively expand archives (an entry of an archive could be also an archive). 

Sensitive Code Example
using var zipToOpen = new FileStream(@"ZipBomb.zip", FileMode.Open);
using var archive = new ZipArchive(zipToOpen, ZipArchiveMode.Read);
foreach (ZipArchiveEntry entry in archive.Entries)
{
  entry.ExtractToFile("./output_onlyfortesting.txt", true); // Sensitive
}

Compliant Solution
int THRESHOLD_ENTRIES = 10000;
int THRESHOLD_SIZE = 1000000000; // 1 GB
double THRESHOLD_RATIO = 10;
int totalSizeArchive = 0;
int totalEntryArchive = 0;

using var zipToOpen = new FileStream(@"ZipBomb.zip", FileMode.Open);
using var archive = new ZipArchive(zipToOpen, ZipArchiveMode.Read);
foreach (ZipArchiveEntry entry in archive.Entries)
{
  totalEntryArchive ++;

  using (Stream st = entry.Open())
  {
    byte[] buffer = new byte[1024];
    int totalSizeEntry = 0;
    int numBytesRead = 0;

    do
    {
      numBytesRead = st.Read(buffer, 0, 1024);
      totalSizeEntry += numBytesRead;
      totalSizeArchive += numBytesRead;
      double compressionRatio = totalSizeEntry / entry.CompressedLength;

      if(compressionRatio > THRESHOLD_RATIO) {
        // ratio between compressed and uncompressed data is highly suspicious, looks like a Zip Bomb Attack
        break;
      }
    }
    while (numBytesRead > 0);
  }

  if(totalSizeArchive > THRESHOLD_SIZE) {
      // the uncompressed data size is too much for the application resource capacity
      break;
  }

  if(totalEntryArchive > THRESHOLD_ENTRIES) {
      // too much entries in this archive, can lead to inodes exhaustion of the system
      break;
  }
}

See

   OWASP - Top 10 2021 Category A1 - Broken Access Control 
   OWASP - Top 10 2021 Category A5 - Security Misconfiguration 
   OWASP - Top 10 2017 Category A5 - Broken Access Control
  
   OWASP - Top 10 2017 Category A6 - Security
  Misconfiguration 
   CWE - CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification) 
   bamsoftware.com - A better Zip Bomb