Local privilege escalation via rq_qos teardown race
Published Dec 9, 2025 · Updated Aug 5, 2026
Race condition in the Linux kernel block rq_qos subsystem allows local users to gain kernel-level privileges through cgroupfs. The subsystem updates q->rq_qos while del_gendisk tears it down, enabling null dereferences, stale-pointer access, and memory corruption. Exploitation requires low-privileged access to a delegated cgroup v2 subtree and control of block-device removal; success compromises the kernel or crashes the host.
Summary
What happened
Race condition in the Linux kernel block rq_qos subsystem allows local users to gain kernel-level privileges through cgroupfs. The subsystem updates q->rq_qos while del_gendisk tears it down, enabling null dereferences, stale-pointer access, and memory corruption. Exploitation requires low-privileged access to a delegated cgroup v2 subtree and control of block-device removal; success compromises the kernel or crashes the host.
The record
- CVE
- CVE-2023-53823
- Published
- Dec 9, 2025
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 9, 2025CVE publishedPublication date reported by the CVE source.
- Aug 5, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=50e34d78815e474d410f342fbe783b18192ca518 <16398b4638b5cd8c1dc95fc940a1591a801d53ce
- Affected versionversion=50e34d78815e474d410f342fbe783b18192ca518 <a13bd91be22318768d55470cbc0b0f4488ef9edf
- Affected versionversion=5.18.8 <5.19
- Affected versionversion=5.19
- Affected versionversion=f28699fafc047ec33299da01e928c3a0073c5cc6
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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