CVE-2024-40445
📋 TL;DR
A directory traversal vulnerability in forkosh Mime TeX allows attackers on Windows systems to read or append arbitrary files by manipulating input paths. This affects users running Mime TeX versions before 1.77 on Windows, potentially exposing sensitive system files.
💻 Affected Systems
- forkosh Mime TeX
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through reading sensitive files (passwords, configuration files) or appending malicious content to critical system files.
Likely Case
Unauthorized file access leading to information disclosure of sensitive data stored in accessible directories.
If Mitigated
Limited impact if proper file permissions and input validation are in place, restricting access to non-critical files.
🎯 Exploit Status
Public proof-of-concept code and demonstration videos are available, making exploitation straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.77
Vendor Advisory: https://github.com/Oefenweb/mimetex
Restart Required: No
Instructions:
1. Download Mime TeX version 1.77 or later from the official repository. 2. Replace the vulnerable mimetex.c file with the patched version. 3. Recompile the application if using source code. 4. Replace the binary if using pre-compiled versions.
🔧 Temporary Workarounds
Input Validation Filter
allImplement strict input validation to reject paths containing directory traversal sequences (../, ..\)
Implement input sanitization in application code before passing paths to Mime TeX
File Permission Restriction
windowsRun Mime TeX with minimal file system permissions, restricting access to necessary directories only
Configure application to run under a restricted user account with limited file access
🧯 If You Can't Patch
- Isolate the vulnerable system from untrusted networks and users
- Implement strict network access controls and monitor for suspicious file access patterns
🔍 How to Verify
Check if Vulnerable:
Check if Mime TeX version is below 1.77 and running on Windows. Review code for vulnerable path handling in mimetex.c lines 12414-12423.Check Version:
Check the version number in the mimetex.c source file or binary metadataVerify Fix Applied:
Verify Mime TeX version is 1.77 or later. Test with directory traversal payloads to confirm they are rejected.📡 Detection & Monitoring
Log Indicators:
- Unusual file access patterns, especially attempts to access files outside expected directories
- Failed path traversal attempts in application logs
Network Indicators:
- HTTP requests containing directory traversal sequences (../, ..\) to Mime TeX endpoints
SIEM Query:
Search for patterns like '*../*' or '*..\\*' in web request logs targeting Mime TeX endpoints