CVE-2021-31663
📋 TL;DR
This buffer overflow vulnerability in RIOT-OS allows attackers to read beyond allocated memory boundaries, potentially exposing sensitive information like cryptographic keys or system data. It affects RIOT-OS 2021.01 installations before commit bc59d60be60dfc0a05def57d74985371e4f22d79. IoT devices running vulnerable RIOT-OS versions are primarily at risk.
💻 Affected Systems
- RIOT-OS
📦 What is this software?
Riot by Riot Os
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through information disclosure leading to privilege escalation or remote code execution via chained attacks.
Likely Case
Information disclosure of adjacent memory contents, potentially exposing sensitive data like encryption keys or configuration details.
If Mitigated
Limited impact with proper memory protection mechanisms and network segmentation in place.
🎯 Exploit Status
Buffer overflow (CWE-120) typically requires specific conditions to trigger but can be exploited without authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Commit bc59d60be60dfc0a05def57d74985371e4f22d79 or later
Vendor Advisory: https://github.com/RIOT-OS/RIOT/commit/bc59d60be60dfc0a05def57d74985371e4f22d79
Restart Required: Yes
Instructions:
1. Update RIOT-OS to commit bc59d60be60dfc0a05def57d74985371e4f22d79 or later
2. Rebuild and redeploy firmware
3. Restart affected devices
🔧 Temporary Workarounds
Network Segmentation
allIsolate RIOT-OS devices from untrusted networks to limit attack surface
Memory Protection
allEnable hardware memory protection features if supported by the microcontroller
🧯 If You Can't Patch
- Segment network to isolate vulnerable devices from critical systems
- Implement strict network access controls and monitor for anomalous memory access patterns
🔍 How to Verify
Check if Vulnerable:
Check RIOT-OS git commit hash against bc59d60be60dfc0a05def57d74985371e4f22d79Check Version:
git log --oneline -1Verify Fix Applied:
Verify commit hash is bc59d60be60dfc0a05def57d74985371e4f22d79 or later📡 Detection & Monitoring
Log Indicators:
- Memory access violations
- Unexpected process crashes
- Out-of-bounds memory reads
Network Indicators:
- Unusual network traffic to RIOT-OS devices
- Protocol anomalies
SIEM Query:
source="riot-os" AND (event_type="memory_violation" OR event_type="crash")🔗 References
- https://github.com/RIOT-OS/RIOT/commit/bc59d60be60dfc0a05def57d74985371e4f22d79
- https://github.com/RIOT-OS/RIOT/issues/15927
- https://github.com/RIOT-OS/RIOT/pull/15929
- https://github.com/RIOT-OS/RIOT/commit/bc59d60be60dfc0a05def57d74985371e4f22d79
- https://github.com/RIOT-OS/RIOT/issues/15927
- https://github.com/RIOT-OS/RIOT/pull/15929
