CVE-2024-8947
📋 TL;DR
This critical vulnerability in MicroPython's objarray component allows attackers to trigger a use-after-free condition when bytes objects are resized and copied into themselves. This could potentially lead to memory corruption, crashes, or arbitrary code execution. Any system running MicroPython 1.22.2 or earlier versions with the vulnerable code is affected.
💻 Affected Systems
- MicroPython
📦 What is this software?
Micropython by Micropython
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or persistent backdoor installation.
Likely Case
Application crashes, denial of service, or memory corruption leading to unstable behavior.
If Mitigated
Minimal impact if proper memory protections and exploit mitigations are in place.
🎯 Exploit Status
Attack can be launched remotely but exploitation appears difficult according to vulnerability description.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.23.0
Vendor Advisory: https://github.com/micropython/micropython/releases/tag/v1.23.0
Restart Required: Yes
Instructions:
1. Download MicroPython 1.23.0 from official repository. 2. Replace existing MicroPython installation with new version. 3. Restart any services or devices using MicroPython.
🔧 Temporary Workarounds
Avoid bytes object self-copy operations
allModify application code to avoid resizing and copying bytes objects into themselves
🧯 If You Can't Patch
- Implement strict input validation to prevent malicious bytes object manipulation
- Deploy memory protection mechanisms like ASLR and DEP to reduce exploit success
🔍 How to Verify
Check if Vulnerable:
Check MicroPython version with 'import sys; print(sys.version)' - if version is 1.22.2 or earlier, system is vulnerable.Check Version:
import sys; print(sys.version)Verify Fix Applied:
After upgrade, verify version is 1.23.0 or later using same command.📡 Detection & Monitoring
Log Indicators:
- Application crashes
- Memory access violation errors
- Unexpected process termination
Network Indicators:
- Unusual network traffic to MicroPython services
- Exploit attempt patterns
SIEM Query:
source="*micropython*" AND (event_type="crash" OR event_type="memory_error")🔗 References
- https://github.com/micropython/micropython/commit/4bed614e707c0644c06e117f848fa12605c711cd
- https://github.com/micropython/micropython/issues/13283
- https://github.com/micropython/micropython/issues/13283#issuecomment-1918479709
- https://github.com/micropython/micropython/releases/tag/v1.23.0
- https://vuldb.com/?ctiid.277765
- https://vuldb.com/?id.277765
- https://vuldb.com/?submit.409316
