CVE-2022-50616: 
Linux Kernel vulnerability analysis and mitigation

CVE-2022-50616 is a Use-After-Free (UAF) vulnerability in the Linux kernel's regulator core subsystem, specifically in the regulator_register function's handling of device tree (DT) init data allocation. The flaw arises from a race condition between MFD (Multi-Function Device) parent device teardown and regulator child device initialization, where init_data allocated to the parent device can be freed while the regulator core is still accessing it. Affected Linux kernel versions span from the initial commit (1da177e4c3f4) up to the fixes introduced in kernel 6.0.16, 6.1.2, and 6.2. It was formally published as a CVE on December 8, 2025, with a CVSS v3.1 base score of 7.0 (High) (Red Hat Advisory, Red Hat Bugzilla).

The root cause is a Use-After-Free (CWE-416) triggered by a race condition (CWE-362) in the Linux kernel's regulator_register() function. When an MFD driver (e.g., mt6370) creates a child regulator device, the child passes its parent device as the parameter for DT init data lookup via regulator_of_get_init_data(), causing the init_data to be allocated under the parent's device resource (devres) rather than the child's. If the parent device is concurrently unregistered (e.g., via i2c_unregister_device() → device_del() → devres_release_all()), the init_data is freed while CPU B's regulator_register() call on the child device continues to reference it, resulting in a UAF. The fix expands the regulator_register API to accept separate devices for resource allocation and DT lookup, ensuring init_data is tied to the child device's lifetime (Red Hat Bugzilla, Red Hat Advisory).

Successful exploitation of this vulnerability can result in high confidentiality, integrity, and availability impact on the affected system. A local attacker with low privileges who can trigger the race condition may achieve arbitrary code execution or cause a kernel panic/crash by manipulating freed memory. The vulnerability is confined to the local system (scope unchanged), but kernel-level code execution could enable privilege escalation and full system compromise (Red Hat Advisory).

No public proof-of-concept exploit code or in-the-wild exploitation has been reported for CVE-2022-50616. The vulnerability requires local access with low privileges and has high attack complexity due to the race condition timing requirement, making reliable exploitation difficult. The EPSS score is approximately 0.017% (0.000170), indicating a very low probability of exploitation in the near term. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog (Red Hat Advisory).

The vulnerability is fixed in Linux kernel versions 6.0.16, 6.1.2, and 6.2, via patches to the regulator_register API (commits 8f3cbcd6b440, b0f25ca1ff9b, and cb29811d989b for the respective stable branches). Users should update to a patched kernel version as soon as possible. No specific configuration-based workaround is available; the primary remediation is applying the upstream kernel patch or upgrading to a distribution kernel that includes the fix (Red Hat Bugzilla, Red Hat Advisory).