CVE-2026-118052 in ThreadX
Summary
by MITRE • 11/02/2026
In Eclipse ThreadX versions 6.0.1 through 6.5.2.202603, the Module Manager loaders return an overflow error without releasing the Module Manager mutex when a module preamble declares a data or stack size that overflows the allocation arithmetic. Loading such an image blocks every later module load, start, stop and unload from other threads until the system is reset.
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Analysis
by VulDB Data Team • 11/02/2026
The vulnerability identified in Eclipse ThreadX versions 6.0.1 through 6.5.2.202603 represents a critical resource management failure within the Module Manager subsystem. This real-time operating system component is responsible for loading, starting, stopping, and unloading modules dynamically at runtime. The core technical flaw lies in the error handling logic of the module loaders when processing module preambles that declare data or stack sizes exceeding available allocation arithmetic limits. Instead of performing a clean rollback to restore system consistency upon detecting such an overflow condition, the loader fails to release the Module Manager mutex. This locking mechanism is essential for ensuring thread-safe access to shared kernel structures during dynamic module operations. By leaving this lock held indefinitely after encountering an error, the implementation creates a persistent deadlock state that affects all subsequent interactions with the module manager.
The operational impact of this flaw is severe and systemic rather than isolated to a single process or task. Because the Module Manager mutex remains locked by the thread that encountered the overflow error, any other thread attempting to perform operations such as loading new modules, starting existing ones, stopping execution, or unloading images will block indefinitely waiting for the lock to be released. This effectively freezes the dynamic module capabilities of the entire system. In embedded and real-time environments where ThreadX is commonly deployed, this can lead to a complete loss of functionality if critical services rely on dynamic loading. The only current resolution requires a full system reset, which may not be feasible or desirable in many safety-critical applications that require high availability and graceful degradation rather than hard resets.
From a classification perspective, this vulnerability aligns with CWE-667, Improper Locking, as the root cause is the failure to properly release a lock after an error condition occurs. It also relates to CWE-400, Uncontrolled Resource Consumption, because the locked mutex consumes system resources and prevents other threads from making progress, effectively causing a denial of service for module-related operations. In terms of attack vectors, this could be exploited by an attacker who can influence or inject modules with malformed preambles that trigger the overflow condition. This maps to MITRE ATT&CK techniques involving resource hijacking or denial of service against specific system components, particularly in contexts where dynamic loading is used for plugin architectures or over-the-air updates.
Mitigation strategies must address both immediate remediation and long-term architectural improvements. The primary solution is to upgrade Eclipse ThreadX to a version later than 6.5.2.202603, where the Module Manager loaders have been patched to correctly release the mutex even when allocation arithmetic overflows are detected. For systems that cannot immediately update the kernel, developers should implement defensive programming practices by validating module preamble sizes before invoking loader functions if possible, although this may not fully mitigate the risk if the validation logic itself is flawed or bypassed. Additionally, implementing watchdog timers with reset capabilities can provide a fallback mechanism to recover from such deadlocks in production environments where immediate patching is not feasible. Security audits should also review other areas of the kernel for similar patterns of improper lock release during error handling paths to prevent analogous vulnerabilities elsewhere in the system.