CVE-2025-5868

Kernel crash via unchecked syscall array index

Published Jun 9, 2025 · Updated Jun 9, 2025

Improper array-index validation in RT-Thread 5.1.0 allows local users to crash the kernel through sys_thread_sigprocmask. The syscall passes the user-controlled how value directly to mask_command_u2k[how] without checking that the index is within the array bounds. A compromised user thread must invoke the syscall with an out-of-range value; the public report demonstrates a kernel-crash path but no working unauthorized-memory-access exploit.

CVSS severity9.8
Critical
EPSS probability1.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper array-index validation in RT-Thread 5.1.0 allows local users to crash the kernel through sys_thread_sigprocmask. The syscall passes the user-controlled how value directly to mask_command_u2k[how] without checking that the index is within the array bounds. A compromised user thread must invoke the syscall with an out-of-range value; the public report demonstrates a kernel-crash path but no working unauthorized-memory-access exploit.

The record

CVE
CVE-2025-5868
Published
Jun 9, 2025
Updated
Jun 9, 2025
Vendor
RT-Thread
Product
RT-Thread
Classifications
CWE-119, CWE-129, T1499.004
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Jun 9, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 9, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.1.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

RT-Thread · RT-Threadversion=5.1.0

Published CVSS scores

8.6VulDBCVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
8.0VulDBCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.4VulDBAV:A/AC:M/Au:S/C:C/I:C/A:C
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
CWE-129Improper Validation of Array Index
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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