CVE-2025-5869 Overview
A critical memory corruption vulnerability has been discovered in RT-Thread version 5.1.0, affecting the sys_recvfrom function within the file rt-thread/components/lwp/lwp_syscall.c. This vulnerability allows an attacker to manipulate the from argument, leading to memory corruption that could potentially result in code execution or system compromise.
Critical Impact
Memory corruption in the lightweight process (LWP) syscall component can lead to arbitrary code execution, system instability, or complete device takeover in embedded systems running RT-Thread.
Affected Products
- RT-Thread 5.1.0
- RT-Thread operating system with LWP (Lightweight Process) component enabled
- Embedded devices and IoT systems utilizing RT-Thread RTOS
Discovery Timeline
- 2025-06-09 - CVE-2025-5869 published to NVD
- 2025-07-11 - Last updated in NVD database
Technical Details for CVE-2025-5869
Vulnerability Analysis
This vulnerability affects the sys_recvfrom function in the RT-Thread Lightweight Process (LWP) syscall implementation. The LWP component provides POSIX-like process management capabilities to RT-Thread, enabling user-space applications to run on the real-time operating system. The sys_recvfrom function is responsible for receiving data from a socket and storing the sender's address information.
The vulnerability stems from improper bounds checking when handling the from argument in the syscall, classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). When a malformed or crafted from argument is passed to the function, the system fails to properly validate memory boundaries, leading to memory corruption.
The attack requires adjacent network access with low complexity and low privileges, making it exploitable by authenticated attackers on the same network segment. Successful exploitation can result in high impact to confidentiality, integrity, and availability of the affected system.
Root Cause
The root cause is a buffer boundary restriction failure (CWE-119) in the sys_recvfrom syscall handler. The function does not adequately validate the size and boundaries of the from argument before writing address information to the user-space buffer. This allows an attacker to trigger out-of-bounds memory operations by providing specially crafted input parameters, corrupting adjacent memory regions.
Attack Vector
The vulnerability is exploitable via an adjacent network attack vector. An attacker with local network access and low-level privileges can craft malicious socket operations that invoke the vulnerable sys_recvfrom syscall with manipulated arguments. The attack does not require user interaction and can be executed with low complexity.
The attacker would need to:
- Gain access to the same network segment as the target RT-Thread device
- Authenticate with minimal privileges to the system
- Execute a user-space application that makes socket syscalls
- Craft malicious recvfrom operations with manipulated from argument values
- Trigger memory corruption to achieve code execution or denial of service
The vulnerability exists in the kernel-level syscall handler, meaning successful exploitation can have severe consequences including privilege escalation and arbitrary code execution at the kernel level.
Detection Methods for CVE-2025-5869
Indicators of Compromise
- Unexpected system crashes or reboots in RT-Thread devices with LWP enabled
- Abnormal memory usage patterns or memory allocation failures
- Suspicious network socket operations from user-space applications
- Core dumps or fault conditions in the lwp_syscall.c component
Detection Strategies
- Monitor RT-Thread devices for unexpected behavior or system instability
- Implement network monitoring to detect anomalous socket communication patterns on adjacent network segments
- Review system logs for syscall-related faults or memory access violations
- Deploy runtime memory protection mechanisms where supported by the hardware
Monitoring Recommendations
- Enable RT-Thread debugging features to capture syscall traces during development and testing
- Implement hardware watchdog timers to detect and recover from system hangs
- Monitor network traffic to and from RT-Thread devices for unusual patterns
- Consider deploying SentinelOne Singularity for IoT to gain visibility into embedded device behavior
How to Mitigate CVE-2025-5869
Immediate Actions Required
- Review your RT-Thread deployment to identify devices running version 5.1.0
- Assess whether LWP functionality is required for your application
- If LWP is not needed, consider disabling the component to eliminate the attack surface
- Restrict adjacent network access to RT-Thread devices using network segmentation
- Monitor the RT-Thread GitHub repository for official patches
Patch Information
At the time of publication, users should monitor the official RT-Thread GitHub repository and issue tracker for patch releases. The vulnerability has been documented in GitHub Issue #10304. Review the VulDB entry for additional technical details and updates on remediation.
Workarounds
- Disable the LWP component if user-space process support is not required for your application
- Implement network segmentation to restrict adjacent network access to vulnerable devices
- Apply strict access controls to limit which applications can execute socket syscalls
- Consider implementing additional input validation in application-level code before invoking socket operations
# RT-Thread configuration example - disable LWP if not required
# In rtconfig.h or using menuconfig
# RT_USING_LWP should be undefined to disable LWP
# #define RT_USING_LWP
# Verify LWP status in configuration
grep -r "RT_USING_LWP" rtconfig.h
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
