CVE-2024-35420
📋 TL;DR
CVE-2024-35420 is a heap overflow vulnerability in wac (WebAssembly Compiler) that allows attackers to write beyond allocated memory boundaries. This could lead to arbitrary code execution or denial of service. Anyone using vulnerable versions of wac is affected.
💻 Affected Systems
- wac (WebAssembly Compiler)
📦 What is this software?
Wac by Kanaka
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Application crash causing denial of service, potentially with memory corruption that could be leveraged for further exploitation.
If Mitigated
Controlled crash with minimal impact if proper memory protections and exploit mitigations are in place.
🎯 Exploit Status
Proof of concept available in GitHub references; heap overflow vulnerabilities are commonly weaponized.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after commit 385e1
Vendor Advisory: https://github.com/kanaka/wac/issues/20
Restart Required: No
Instructions:
1. Update wac to latest version from GitHub repository. 2. Recompile any affected WebAssembly code with patched version.
🔧 Temporary Workarounds
Disable wac usage
allTemporarily stop using wac for WebAssembly compilation until patched.
🧯 If You Can't Patch
- Implement strict input validation and sanitization for WebAssembly code processed by wac.
- Deploy memory protection mechanisms like ASLR and DEP to reduce exploit success.
🔍 How to Verify
Check if Vulnerable:
Check wac version or commit hash; if using commit 385e1 or earlier, it's vulnerable.Check Version:
wac --version or check git commit hash in repository.Verify Fix Applied:
Verify wac version is updated beyond commit 385e1 and test with known malicious inputs.📡 Detection & Monitoring
Log Indicators:
- Unexpected wac process crashes
- Memory access violation errors in system logs
Network Indicators:
- Unusual network traffic to/from wac processes
SIEM Query:
Process: wac AND (EventID: 1000 OR EventID: 1001) OR Memory: AccessViolation