CVE-2020-7788
📋 TL;DR
CVE-2020-7788 is a prototype pollution vulnerability in the ini npm package that allows attackers to modify object prototypes by submitting malicious INI files. This affects any application using ini.parse() with affected versions, potentially leading to denial of service, remote code execution, or privilege escalation depending on how the polluted objects are used.
💻 Affected Systems
- ini npm package
📦 What is this software?
Ini by Ini Project
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution or complete system compromise if polluted objects are used in security-critical contexts like authentication or command execution.
Likely Case
Denial of service, application crashes, or data corruption from prototype pollution disrupting normal object behavior.
If Mitigated
Limited impact with proper input validation and sandboxing, potentially only causing application instability.
🎯 Exploit Status
Exploitation requires submitting a malicious INI file to an application using vulnerable ini.parse(). Proof-of-concept examples are publicly available showing prototype pollution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.3.6 and later
Vendor Advisory: https://github.com/npm/ini/commit/56d2805e07ccd94e2ba0984ac9240ff02d44b6f1
Restart Required: Yes
Instructions:
1. Update ini package to version 1.3.6 or later using npm update ini. 2. Restart all applications using the ini package. 3. Test application functionality with updated package.
🔧 Temporary Workarounds
Input validation and sanitization
allImplement strict validation of INI file content before parsing, rejecting files with suspicious patterns.
Use Object.create(null) for parsed objects
allModify code to create objects without prototypes when using ini.parse() results.
🧯 If You Can't Patch
- Implement strict file upload controls and only accept INI files from trusted sources
- Sandbox applications using ini.parse() to limit potential damage from exploitation
🔍 How to Verify
Check if Vulnerable:
Check package.json or run npm list ini to see installed version. If version is below 1.3.6, the system is vulnerable.Check Version:
npm list ini | grep iniVerify Fix Applied:
After updating, verify npm list ini shows version 1.3.6 or higher and test parsing known malicious INI files to ensure no prototype pollution occurs.📡 Detection & Monitoring
Log Indicators:
- Application crashes or unexpected behavior after parsing INI files
- Error logs showing prototype-related errors
- Unusual file upload patterns for INI files
Network Indicators:
- Uploads of INI files to web applications
- POST requests with INI content to API endpoints
SIEM Query:
source="application_logs" AND ("ini.parse" OR "INI parsing") AND (error OR crash OR exception)🔗 References
- https://github.com/npm/ini/commit/56d2805e07ccd94e2ba0984ac9240ff02d44b6f1
- https://lists.debian.org/debian-lts-announce/2020/12/msg00032.html
- https://snyk.io/vuln/SNYK-JS-INI-1048974
- https://github.com/npm/ini/commit/56d2805e07ccd94e2ba0984ac9240ff02d44b6f1
- https://lists.debian.org/debian-lts-announce/2020/12/msg00032.html
- https://snyk.io/vuln/SNYK-JS-INI-1048974
