CVE-2024-27527
📋 TL;DR
CVE-2024-27527 is a denial-of-service vulnerability in wasm3 WebAssembly interpreter where specially crafted WASM modules can cause infinite loops or excessive resource consumption, crashing the interpreter. This affects any application using wasm3 to execute untrusted WebAssembly code. The vulnerability requires an attacker to supply malicious WASM modules to the interpreter.
💻 Affected Systems
- wasm3
📦 What is this software?
Wasm3 by Wasm3 Project
⚠️ Risk & Real-World Impact
Worst Case
Complete service disruption where the wasm3 interpreter crashes or becomes unresponsive, potentially affecting the entire application using it.
Likely Case
Application instability or crashes when processing malicious WASM modules, leading to service interruptions.
If Mitigated
Limited impact if only trusted WASM modules are executed or if resource limits are strictly enforced.
🎯 Exploit Status
Proof-of-concept available in GitHub issue. Exploitation requires ability to supply WASM modules to the interpreter.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Commit after 139076a (check latest master)
Vendor Advisory: https://github.com/wasm3/wasm3/issues/464
Restart Required: Yes
Instructions:
1. Update wasm3 to latest commit from master branch. 2. Rebuild your application with the updated wasm3 library. 3. Restart any services using wasm3.
🔧 Temporary Workarounds
Limit WASM module sources
allOnly execute WASM modules from trusted sources
Implement resource limits
allSet execution timeouts and memory limits for WASM module execution
🧯 If You Can't Patch
- Isolate wasm3 execution in sandboxed environments with strict resource constraints
- Implement input validation to reject suspicious WASM modules before execution
🔍 How to Verify
Check if Vulnerable:
Check if your wasm3 version includes commit 139076a or earlier. Run: git log --oneline | grep 139076aCheck Version:
git log --oneline -1Verify Fix Applied:
Verify you're using a commit after 139076a. Test with known malicious WASM modules from the PoC.📡 Detection & Monitoring
Log Indicators:
- Process crashes of wasm3 interpreter
- High CPU usage spikes from wasm3 processes
- Application errors related to WASM execution
Network Indicators:
- Unusually large or frequent WASM module uploads to services using wasm3
SIEM Query:
process.name:"wasm3" AND (event.action:"crash" OR cpu.usage > 90)