CVE-2017-1000047
📋 TL;DR
CVE-2017-1000047 is a directory traversal vulnerability in rbenv that allows attackers to specify arbitrary Ruby version paths, potentially leading to arbitrary code execution. This affects all current versions of rbenv at the time of disclosure. Users who install Ruby versions from untrusted sources or work in multi-user environments are particularly vulnerable.
💻 Affected Systems
- rbenv
📦 What is this software?
Rbenv by Rbenv Project
⚠️ 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
Full system compromise via arbitrary code execution with the privileges of the user running rbenv commands, potentially leading to privilege escalation.
Likely Case
Local privilege escalation in multi-user systems or code execution when users install Ruby versions from malicious sources.
If Mitigated
Limited impact if users only install Ruby versions from trusted sources and maintain proper file permissions.
🎯 Exploit Status
Exploitation requires the ability to specify Ruby version strings, typically through user interaction or malicious Ruby version installation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Updated versions with security fixes (check rbenv repository)
Vendor Advisory: https://github.com/rbenv/rbenv/security/advisories
Restart Required: No
Instructions:
1. Update rbenv to the latest version from the official repository. 2. Run 'rbenv rehash' to update shims. 3. Verify the fix by testing directory traversal attempts.
🔧 Temporary Workarounds
Restrict Ruby version sources
allOnly install Ruby versions from trusted, official sources and avoid using version strings from untrusted inputs.
File permission hardening
linuxEnsure proper file permissions on rbenv directories and Ruby installations to limit potential damage.
chmod 755 ~/.rbenv
chmod 755 ~/.rbenv/versions
🧯 If You Can't Patch
- Implement strict input validation for Ruby version specifications in any custom scripts or applications.
- Monitor for suspicious file access patterns in rbenv directories and Ruby version installations.
🔍 How to Verify
Check if Vulnerable:
Test if rbenv accepts directory traversal sequences in version strings, such as '../' patterns.Check Version:
rbenv --versionVerify Fix Applied:
Attempt to use directory traversal in Ruby version specification and verify it's rejected or properly sanitized.📡 Detection & Monitoring
Log Indicators:
- Unusual file access patterns in rbenv directories
- Execution of unexpected Ruby versions or paths
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
Search for process execution events with unusual paths containing directory traversal sequences in Ruby-related commands.