CVE-2025-51824
📋 TL;DR
CVE-2025-51824 is a buffer overflow vulnerability in libcsp 2.0's csp_usart_open() function that could allow attackers to execute arbitrary code or cause denial of service. This affects systems using libcsp for CubeSat Space Protocol communication, particularly those with Zephyr RTOS drivers. Embedded systems and IoT devices implementing this protocol stack are at risk.
💻 Affected Systems
- libcsp
📦 What is this software?
Libcsp by Libcsp
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data exfiltration, or persistent backdoor installation.
Likely Case
Denial of service through system crashes or reboots, potentially disrupting critical communication functions.
If Mitigated
Limited impact with proper memory protection mechanisms and exploit mitigations in place.
🎯 Exploit Status
Exploitation requires sending specially crafted data to the vulnerable USART interface. No public exploits available as of analysis.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: libcsp 2.0.1 or later
Vendor Advisory: https://github.com/libcsp/libcsp/issues/851
Restart Required: No
Instructions:
1. Update libcsp to version 2.0.1 or later. 2. Apply the fix from pull request #853. 3. Recompile and redeploy affected applications.
🔧 Temporary Workarounds
Disable vulnerable USART functionality
allDisable or restrict access to the affected USART driver if not required for system operation.
Modify system configuration to disable CONFIG_CSP_DRIVER_USART_ZEPHYR
🧯 If You Can't Patch
- Implement strict input validation and bounds checking for USART data processing.
- Deploy network segmentation to isolate vulnerable systems from untrusted networks.
🔍 How to Verify
Check if Vulnerable:
Check libcsp version and verify if using Zephyr USART driver: grep -r 'csp_usart_open' in source code.Check Version:
Check libcsp version in build configuration or via package manager: dpkg -l | grep libcsp or equivalent.Verify Fix Applied:
Verify libcsp version is 2.0.1+ and check that the buffer overflow fix from PR #853 is applied.📡 Detection & Monitoring
Log Indicators:
- Unexpected system crashes or reboots
- Memory access violation errors in system logs
- Abnormal USART communication patterns
Network Indicators:
- Unusual traffic patterns to USART-enabled ports
- Protocol anomalies in CSP communications
SIEM Query:
Search for: 'libcsp crash' OR 'csp_usart_open' OR 'segmentation fault' in system logs