CVE-2022-34736 in Linux
Summary
by MITRE • 07/12/2022
The frame scheduling module has a null pointer dereference vulnerability. Successful exploitation of this vulnerability will affect the kernel availability.
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Analysis
by VulDB Data Team • 07/22/2022
The CVE-2022-34736 vulnerability resides within the frame scheduling module of a kernel-based system, representing a critical null pointer dereference flaw that can compromise system availability. This type of vulnerability typically occurs when software attempts to access memory through a pointer that has not been properly initialized or has been set to null, leading to system crashes or unexpected behavior. The frame scheduling module is responsible for managing how tasks or processes are scheduled across system resources, making this particular vulnerability especially dangerous as it directly impacts the kernel's ability to maintain system stability and operational continuity.
The technical nature of this vulnerability stems from inadequate input validation and error handling within the kernel's scheduling subsystem. When the frame scheduling module processes certain inputs or conditions, it fails to properly validate pointer references before attempting to dereference them, creating a scenario where a null pointer is accessed. This flaw aligns with CWE-476, which specifically addresses null pointer dereference vulnerabilities, and represents a classic example of improper handling of uninitialized or invalid memory references. The vulnerability manifests as a kernel panic or system crash when the scheduler attempts to process frame scheduling requests that trigger the null pointer access condition.
From an operational impact perspective, successful exploitation of this vulnerability can result in complete system unavailability and denial of service conditions. The kernel's frame scheduling module is fundamental to system operation, as it determines how computational resources are allocated to various processes and tasks. When this module fails due to null pointer dereference, the entire system may become unresponsive, requiring manual intervention or system reboot to restore functionality. This type of vulnerability is particularly concerning in production environments where system uptime and reliability are paramount, as it can lead to extended service disruptions and potential data loss. The impact extends beyond simple system crashes, as it can affect critical infrastructure, embedded systems, and real-time applications that depend on predictable scheduling behavior.
Mitigation strategies for CVE-2022-34736 should focus on both immediate patching and defensive measures. Organizations must prioritize applying vendor-provided security patches that address the null pointer dereference in the frame scheduling module, as these fixes typically involve proper pointer validation and initialization checks. System administrators should implement monitoring solutions to detect unusual system behavior or kernel panic events that may indicate exploitation attempts. The vulnerability's characteristics align with ATT&CK technique T1499.004, which covers system shutdown/reboot attacks, as the exploitation results in system availability disruption. Additionally, implementing kernel hardening measures such as stack canaries, address space layout randomization, and kernel address space protection can help reduce the exploitability of similar vulnerabilities. Regular security assessments and kernel integrity monitoring should be conducted to identify potential exploitation attempts and maintain overall system security posture.