CVE-2026-74405

Received Received - Intake

Race Condition in Linux Kernel OPP Subsystem

Publication date: 2026-08-15

Last updated on: 2026-08-17

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: OPP: Fix race between OPP addition and lookup A race exists between dev_pm_opp_add_dynamic() and dev_pm_opp_find_freq_exact(): CPU0 (add) CPU1 (lookup) ------------------------------- ------------------------------ _opp_add() mutex_lock() list_add(&new_opp->node, head) mutex_unlock() _opp_table_find_key() mutex_lock() dev_pm_opp_get(opp) kref_get() mutex_unlock() kref_init(&new_opp->kref) dev_pm_opp_put() kref_put_mutex() The newly added OPP is inserted into the list before its kref is initialized. A concurrent lookup can find this OPP and increment its reference count while it is still uninitialized, leading to refcount corruption and a potential premature free. Fix this by initializing ->kref and ->opp_table before making the OPP visible via list_add(). This ensures any concurrent lookup observes a fully initialized object. [ Viresh: Updated commit log ]

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-08-15

Last Modified

2026-08-17

Generated

2026-09-04

AI Q&A

2026-08-15

EPSS Evaluated

2026-09-03

NVD

CVE-2026-74405

EUVD

EUVD-2026-59552

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability is a race condition in the Linux kernel's OPP (Operating Performance Points) subsystem. It occurs when a new OPP is added dynamically while another CPU core tries to look it up. The race happens because the OPP is added to a list before its reference counter is initialized, allowing a concurrent lookup to increment an uninitialized counter. This leads to reference count corruption and potential premature freeing of the OPP object.

Detection Guidance

This vulnerability is specific to the Linux kernel's OPP (Operating Performance Points) subsystem and does not have network-based detection methods. Detection requires checking the kernel version and OPP-related code for the race condition fix. Use commands like 'uname -a' to check kernel version and review kernel logs for OPP-related errors.

Impact Analysis

This vulnerability could cause system instability or crashes due to memory corruption. It may lead to unexpected behavior in power management or performance scaling on affected systems. Systems relying on dynamic OPP adjustments for CPU frequency or voltage could experience hangs, reboots, or data corruption if exploited.

Compliance Impact

This vulnerability does not directly affect compliance with standards like GDPR or HIPAA as it is a low-level kernel race condition in the OPP subsystem. It could indirectly impact compliance if exploited to cause system instability or crashes, potentially affecting data processing integrity or availability.

Mitigation Strategies

Update the Linux kernel to a patched version that includes the fix for this race condition. Monitor kernel logs for OPP-related errors or crashes. If immediate patching is not possible, restrict access to systems where OPP operations are critical to reduce exposure.

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