CVE-2022-50729 in Linux
Summary
by MITRE • 12/24/2025
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: Fix resource leak in ksmbd_session_rpc_open()
When ksmbd_rpc_open() fails then it must call ksmbd_rpc_id_free() to undo the result of ksmbd_ipc_id_alloc().
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Analysis
by VulDB Data Team • 04/21/2026
The vulnerability identified as CVE-2022-50729 resides within the Linux kernel's ksmbd subsystem, which provides SMB/CIFS file sharing capabilities for Linux systems. This issue represents a resource management flaw that occurs during the handling of RPC (Remote Procedure Call) sessions within the ksmbd implementation. The ksmbd subsystem serves as a bridge between Linux and Windows SMB/CIFS protocols, enabling file sharing and other network services. When a ksmbd session attempts to open an RPC connection and subsequently fails, the system does not properly release allocated resources, leading to a resource leak that can accumulate over time.
The technical flaw manifests in the ksmbd_session_rpc_open() function where proper resource cleanup is not performed when the ksmbd_rpc_open() operation fails. Specifically, the function allocates resources using ksmbd_ipc_id_alloc() but fails to call the corresponding cleanup function ksmbd_rpc_id_free() when the operation does not complete successfully. This pattern violates fundamental resource management principles and creates a classic resource leak scenario where system memory and potentially other resources remain allocated even after the failed operation. The vulnerability is categorized under CWE-404, which specifically addresses improper resource release or unbalanced resource management, making it a clear violation of proper resource handling practices.
The operational impact of this vulnerability extends beyond simple memory consumption, as the resource leak can progressively degrade system performance and potentially lead to system instability or denial of service conditions. When multiple failed RPC operations occur, the accumulation of unreleased resources can exhaust available system memory or other critical resources, ultimately affecting the overall availability of the ksmbd service. Attackers who can repeatedly trigger failed RPC operations may exploit this vulnerability to cause resource exhaustion, potentially leading to system crashes or making the file sharing service unavailable to legitimate users. The vulnerability is particularly concerning in environments where ksmbd is heavily utilized for network file sharing, as the resource leak can compound over time and affect system reliability.
Mitigation strategies for CVE-2022-50729 focus on ensuring proper resource management practices within the ksmbd subsystem. The primary fix involves modifying the ksmbd_session_rpc_open() function to include proper error handling that calls ksmbd_rpc_id_free() whenever ksmbd_rpc_open() fails, thereby maintaining resource balance. System administrators should apply the relevant kernel patches that address this specific resource leak issue, as these updates ensure that all allocated resources are properly released regardless of operation success or failure. Additionally, monitoring systems should be implemented to track resource usage patterns and detect potential resource exhaustion conditions that may indicate exploitation attempts. Organizations using ksmbd for SMB/CIFS services should conduct regular security assessments and ensure that their kernel versions are up-to-date with the latest security patches. The vulnerability demonstrates the importance of following ATT&CK framework principles for resource management and proper error handling, as it represents a failure in the system's ability to maintain resource integrity during error conditions, potentially enabling adversaries to perform resource exhaustion attacks against the system.