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Rt ThreadOperating system

CVE-2025-5869

CRITICAL · 9.8 CVSS v3.1 Published 2025-06-09
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Public exploit Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A vulnerability, which was classified as critical, was found in RT-Thread 5.1.0. Affected is the function sys_recvfrom of the file rt-thread/components/lwp/lwp_syscall.c. The manipulation of the argument from leads to memory corruption.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A memory corruption vulnerability exists in the sys_recvfrom function within RT-Thread 5.1.0's LWP (LightWeight Process) syscall implementation. The manipulation of the 'from' argument (the socket address buffer) leads to memory corruption, likely due to insufficient bounds checking when copying source address information. This network-related syscall handles datagram reception and the vulnerability is exploitable remotely given the CVSS vector likely indicates network accessibility.

MitigationUpgrade to a patched version of RT-Thread once available. If no patch exists, implement input validation on the from_len parameter and ensure proper bounds checking before writing to the from buffer in sys_recvfrom; consider adding address length validation to prevent buffer overflows.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Rt ThreadOperating system
Affected:= 5.1.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify RT-Thread version
    Check the RT-Thread version by inspecting the version header file (typically rtconfig.h or version.h in the BSP) or running 'pkgs --version' if the package manager is available. Look for version information in build configuration files or the kernel initialization code.
    Affected if The installed version is RT-Thread 5.1.0 exactly, as this is the only affected version listed.
  2. Confirm LWP module is enabled
    Examine the RT-Thread configuration file (rtconfig.h) or Kconfig for the configuration option 'RT_USING_LWP' or 'RT_LWP'. This is typically found in the build configuration directory of the project.
    Affected if LWP (LightWeight Process) support is enabled in the build configuration, as the vulnerability exists in the LWP syscall implementation.
  3. Verify network socket support is active
    Check if network stack is enabled in the RT-Thread configuration by looking for 'RT_USING_LWIP' or similar network stack options in the build configuration files.
    Affected if Network stack is enabled, as the vulnerability resides in the sys_recvfrom network syscall.
  4. Check for datagram socket usage
    Review application source code for calls to recvfrom, recv, or socket() function with SOCK_DGRAM type, which would use the vulnerable sys_recvfrom path.
    Affected if The application creates or uses datagram (UDP) sockets, as the sys_recvfrom function handles datagram reception and the vulnerability is in the from argument handling.
  5. Inspect sys_recvfrom implementation
    Examine the LWP syscall source code in the RT-Thread distribution, specifically the sys_recvfrom function in the LWP implementation files (typically in lwp directory). Look for bounds checking on the 'from' parameter.
    Affected if The sys_recvfrom implementation lacks proper bounds checking on the 'from_len' parameter before writing to the 'from' buffer, indicating the vulnerable code is present.

A system is affected if it runs RT-Thread version 5.1.0 with LWP and network stack enabled, and uses datagram sockets handled by the vulnerable sys_recvfrom implementation.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade to a patched version of RT-Thread once available. If no patch exists, implement input validation on the from_len parameter and ensure proper bounds checking before writing to the from buffer in sys_recvfrom; consider adding address length validation to prevent buffer overflows.

Fix this in Rt Thread Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA8.0 h
44.0 hours of engineering $7,720
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-5869 in production — separate from our analysis above.

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What belongs here
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