CVE-2021-44331
📋 TL;DR
CVE-2021-44331 is a buffer overflow vulnerability in ARM's astcenc 3.2.0 Adaptive Scalable Texture Compression encoder. This vulnerability allows attackers to execute arbitrary code or cause denial of service by providing specially crafted texture files. Anyone using astcenc 3.2.0 to process untrusted texture files is affected.
💻 Affected Systems
- ARM astc-encoder
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise when processing malicious texture files
Likely Case
Application crash or denial of service when processing malformed texture inputs
If Mitigated
Limited impact if only trusted texture sources are processed with proper input validation
🎯 Exploit Status
Proof of concept available in GitHub issue #294; exploitation requires feeding malicious texture files to vulnerable encoder
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 3.3.0 and later
Vendor Advisory: https://github.com/ARM-software/astc-encoder/issues/294
Restart Required: No
Instructions:
1. Update astc-encoder to version 3.3.0 or later. 2. Recompile any applications using astcenc. 3. Replace vulnerable binaries with patched versions.
🔧 Temporary Workarounds
Input validation and sanitization
allImplement strict validation of texture file inputs before processing with astcenc
Sandbox execution
linuxRun astcenc in isolated containers or sandboxes with limited privileges
docker run --read-only --cap-drop=ALL -v /trusted/textures:/input:ro astcenc
🧯 If You Can't Patch
- Restrict astcenc usage to trusted texture sources only
- Implement network segmentation to isolate texture processing systems
🔍 How to Verify
Check if Vulnerable:
Check astcenc version: astcenc --version | grep '3.2.0'Check Version:
astcenc --versionVerify Fix Applied:
Verify version is 3.3.0 or later: astcenc --version📡 Detection & Monitoring
Log Indicators:
- Segmentation faults in astcenc processes
- Abnormal memory usage patterns in texture processing
Network Indicators:
- Unusual texture file uploads to web applications
- Multiple failed texture processing attempts
SIEM Query:
Process:astcenc AND (EventID:1000 OR MemoryUsage>threshold)