CVE-2024-26920 in Linux
Summary
by MITRE • 04/17/2024
In the Linux kernel, the following vulnerability has been resolved:
tracing/trigger: Fix to return error if failed to alloc snapshot
Fix register_snapshot_trigger() to return error code if it failed to allocate a snapshot instead of 0 (success). Unless that, it will register snapshot trigger without an error.
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Analysis
by VulDB Data Team • 09/16/2025
The vulnerability identified as CVE-2024-26920 resides within the Linux kernel's tracing subsystem, specifically affecting the trigger mechanism functionality. This issue manifests in the tracing/trigger component where the register_snapshot_trigger() function fails to properly handle allocation failures for snapshot operations. The flaw represents a critical oversight in error handling that could potentially compromise system integrity and operational reliability. The vulnerability stems from the function's improper return value when memory allocation for snapshots fails, which directly impacts the kernel's ability to maintain consistent and secure tracing operations.
The technical root cause of this vulnerability lies in the improper error propagation mechanism within the kernel's tracing infrastructure. When register_snapshot_trigger() encounters a failure during snapshot allocation, it should return an appropriate error code to indicate the failure condition to the calling function. However, the current implementation incorrectly returns zero, which is interpreted as a successful operation. This misbehavior creates a dangerous scenario where the system continues to register snapshot triggers even when underlying memory allocation has failed, leading to potential memory corruption or undefined behavior. The flaw directly violates proper kernel programming practices and error handling protocols that are fundamental to maintaining system stability.
The operational impact of this vulnerability extends beyond simple error reporting issues and can potentially affect system security and reliability. When snapshot allocation fails but the function still reports success, it allows for inconsistent tracing states that could be exploited by malicious actors or lead to system instability. This particular vulnerability affects the kernel's ability to properly manage tracing resources and could result in resource exhaustion or memory corruption scenarios. The issue particularly impacts systems that rely heavily on kernel tracing for debugging, monitoring, or security auditing purposes, where the integrity of tracing operations is paramount for system security posture.
This vulnerability aligns with CWE-252, which addresses "Unchecked Return Value" conditions, and represents a classic example of improper error handling in kernel space. The flaw also intersects with ATT&CK technique T1566, which covers malicious manipulation of system processes, as incorrect error handling could potentially be leveraged to manipulate kernel operations. The fix implemented addresses this by ensuring that register_snapshot_trigger() properly returns error codes when snapshot allocation fails, thereby maintaining the integrity of the kernel's tracing subsystem. Security practitioners should note that this vulnerability could potentially be exploited in scenarios where attackers attempt to manipulate kernel tracing mechanisms or where resource exhaustion attacks are employed against the kernel's memory management subsystem.
The mitigation strategy for CVE-2024-26920 involves applying the kernel patch that corrects the return value handling in the register_snapshot_trigger() function. System administrators should prioritize updating to kernel versions that include this fix, particularly in environments where kernel tracing is actively used for security monitoring or debugging operations. Organizations should also implement monitoring for unusual tracing behavior or memory allocation patterns that might indicate exploitation attempts. The fix ensures proper error propagation and maintains the kernel's ability to gracefully handle allocation failures, thereby preserving system stability and security. Regular kernel updates and vulnerability assessments remain essential practices for maintaining protection against similar issues in the kernel's tracing infrastructure.