CVE-2025-30358
📋 TL;DR
A class pollution vulnerability in Mesop Python UI framework allows attackers to overwrite global variables and class attributes during runtime. This can lead to denial of service attacks, identity confusion, and potentially remote code execution when combined with available gadgets. All users running Mesop versions prior to 0.14.1 are affected.
💻 Affected Systems
- mesop
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise when combined with available gadgets in the application.
Likely Case
Denial of service attacks disrupting application availability and identity confusion enabling impersonation attacks.
If Mitigated
Limited impact with proper input validation and runtime monitoring, but still vulnerable to DoS.
🎯 Exploit Status
Exploitation requires understanding of Mesop's internal structure and available gadgets for maximum impact.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.14.1
Vendor Advisory: https://github.com/mesop-dev/mesop/security/advisories/GHSA-f3mf-hm6v-jfhh
Restart Required: No
Instructions:
1. Update Mesop using pip: pip install --upgrade mesop==0.14.1
2. Verify the update completed successfully
3. Test application functionality after update
🔧 Temporary Workarounds
Input validation and sanitization
allImplement strict input validation and sanitization for all user-controlled data passed to Mesop components
🧯 If You Can't Patch
- Implement Web Application Firewall (WAF) rules to detect and block suspicious payload patterns
- Isolate vulnerable applications in network segments with strict access controls
🔍 How to Verify
Check if Vulnerable:
Check Mesop version: python -c "import mesop; print(mesop.__version__)" and compare to 0.14.1Check Version:
python -c "import mesop; print(mesop.__version__)"Verify Fix Applied:
Verify version is 0.14.1 or higher using: python -c "import mesop; print(mesop.__version__)"📡 Detection & Monitoring
Log Indicators:
- Unusual class attribute modifications
- Unexpected global variable changes
- Application crashes with class pollution errors
Network Indicators:
- Suspicious payloads containing class manipulation patterns
- Unusual request patterns targeting Mesop endpoints
SIEM Query:
source="application_logs" AND ("class pollution" OR "attribute overwrite" OR "global variable modification")