CVE-2024-26339
📋 TL;DR
CVE-2024-26339 is a critical buffer overflow vulnerability in swftools v0.9.2 caused by a strcpy parameter overlap. This allows attackers to execute arbitrary code or cause denial of service by processing malicious SWF files. Anyone using swftools to process untrusted SWF files is affected.
💻 Affected Systems
- swftools
📦 What is this software?
Swftools by Swftools
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with the privileges of the swftools process, potentially leading to full system compromise.
Likely Case
Denial of service through application crashes when processing malicious SWF files.
If Mitigated
Limited impact if swftools runs in sandboxed environments with minimal privileges.
🎯 Exploit Status
Exploitation requires feeding a malicious SWF file to swftools. No authentication needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: https://github.com/matthiaskramm/swftools/issues/225
Restart Required: No
Instructions:
No official patch exists. Consider workarounds or alternative software.
🔧 Temporary Workarounds
Disable swftools processing
allStop using swftools to process SWF files until a fix is available.
Run swftools in sandbox
linuxRun swftools with minimal privileges in a container or sandboxed environment.
docker run --read-only --cap-drop=ALL -v /path/to/swf:/input:ro swftools
🧯 If You Can't Patch
- Restrict swftools to process only trusted, pre-verified SWF files.
- Monitor swftools process crashes and unexpected behavior as potential exploitation indicators.
🔍 How to Verify
Check if Vulnerable:
Check swftools version: swfrender --version or swfc --versionCheck Version:
swfrender --version 2>&1 | head -1Verify Fix Applied:
No fix available to verify. Monitor GitHub repository for updates.📡 Detection & Monitoring
Log Indicators:
- swftools process crashes
- segmentation faults in swftools logs
Network Indicators:
- Unexpected SWF file uploads to systems running swftools
SIEM Query:
process_name:"swfrender" OR process_name:"swfc" AND (event_type:"crash" OR exit_code:139)