CVE-2026-22870

GuardDog's safe_extract() function does not validate decompressed file sizes when extracting ZIP archives (wheels, eggs), allowing attackers to cause denial of service through zip bombs. A malicious package can consume gigabytes of disk space from a few megabytes of compressed data.

Vulnerability Details

Affected Component: guarddog/utils/archives.py - safe_extract() function
Vulnerability Type: CWE-409 - Improper Handling of Highly Compressed Data (Zip Bomb)
Severity: HIGH (CVSS ~8)
Attack Vector: Network (malicious package uploaded to PyPI/npm) or local

Root Cause

The safe_extract() function handles TAR files securely using the tarsafe library, but ZIP file extraction has no size validation:

elif zipfile.is_zipfile(source_archive):
    with zipfile.ZipFile(source_archive, "r") as zip:
        for file in zip.namelist():
            zip.extract(file, path=os.path.join(target_directory, file))

Missing protections:

• ❌ No decompressed size limit
• ❌ No compression ratio validation
• ❌ No file count limits
• ❌ No total extracted size validation

Denial of Service Scenarios

1. CI/CD Pipeline Disruption

• Attacker publishes malicious package to PyPI
• Developer adds package to requirements.txt
• CI/CD runs GuardDog scan
• Disk fills (GitHub Actions: standard 14GB limit)
• All deployments blocked

2. Resource Exhaustion

• Local development environments
• Security scanning infrastructure
• Automated scanning systems
• Docker containers with limited disk

3. Supply Chain Attack Amplification

• Single malicious package blocks security scanning
• Prevents detection of other malicious packages
• Forces manual intervention
• Increases security team workload

Configuration Options

Make limits configurable via environment variables or config file

Additional Improvements

1. Add warning logs when archives approach limits
2. Provide clear error messages for users
3. Document limits in user-facing documentation
4. Add tests for zip bomb detection
5. Consider using a safe ZIP library (similar to tarsafe)

Credit

Reported by: Charbel (dwbruijn)

Kodem intelligence

Add size validation for ZIP files similar to what tarsafe provides for TAR files

1. What is CVE-2026-22870? CVE-2026-22870 is a high-severity security vulnerability in guarddog (pip), affecting versions < 2.7.1. It is fixed in 2.7.1.
2. Which versions of guarddog are affected by CVE-2026-22870? guarddog (pip) versions < 2.7.1 is affected.
3. Is there a fix for CVE-2026-22870? Yes. CVE-2026-22870 is fixed in 2.7.1. Upgrade to this version or later.
4. Is CVE-2026-22870 exploitable, and should I be worried? Whether CVE-2026-22870 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
5. What actually determines whether CVE-2026-22870 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
6. How do I fix CVE-2026-22870? Upgrade guarddog to 2.7.1 or later.