CVE-2021-46326
📋 TL;DR
CVE-2021-46326 is a heap buffer overflow vulnerability in Moddable SDK v11.5.0 that occurs in the __asan_memcpy component. This vulnerability could allow attackers to execute arbitrary code or cause denial of service by exploiting memory corruption. It affects systems running applications built with the vulnerable Moddable SDK version.
💻 Affected Systems
- Moddable SDK
📦 What is this software?
Moddable Sdk by Moddable
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or persistent backdoor installation.
Likely Case
Application crash causing denial of service, potentially leading to data corruption or service disruption.
If Mitigated
Limited impact with proper memory protection mechanisms and exploit mitigations in place.
🎯 Exploit Status
Heap buffer overflows typically require specific memory layout conditions for reliable exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v11.5.1 and later
Vendor Advisory: https://github.com/Moddable-OpenSource/moddable/issues/759
Restart Required: Yes
Instructions:
1. Update Moddable SDK to version 11.5.1 or later. 2. Rebuild all applications using the updated SDK. 3. Redeploy updated applications to affected systems.
🔧 Temporary Workarounds
Memory Protection Enablement
allEnable ASLR and DEP/ASLR protections at the OS level to make exploitation more difficult
🧯 If You Can't Patch
- Isolate affected applications in network segments with strict access controls
- Implement application allowlisting to prevent unauthorized code execution
🔍 How to Verify
Check if Vulnerable:
Check if applications are built with Moddable SDK v11.5.0 by examining build configurations or checking SDK version in application metadataCheck Version:
Check the SDK version in the moddable directory or build configuration filesVerify Fix Applied:
Verify SDK version is 11.5.1 or later and applications have been rebuilt with the updated SDK📡 Detection & Monitoring
Log Indicators:
- Application crashes with memory access violation errors
- Unexpected process termination
Network Indicators:
- Unusual network connections from affected applications
SIEM Query:
Process termination events from Moddable applications OR memory access violation alerts