Local privilege escalation via repeated unregister notifications
Published May 2, 2025 · Updated Aug 5, 2026
Use-after-free in the CAIF USB driver in Linux allows local users to gain kernel privileges via network namespace teardown. The cfusbl_device_notify() callback processes repeated NETDEV_UNREGISTER notifications, permitting the parent net_device to be freed before a later callback dereferences it. Exploitation requires CAP_NET_ADMIN in a user namespace and CAIF support; controlled heap reuse can disclose or modify kernel memory, while the demonstrated path can panic the kernel.
Summary
What happened
Use-after-free in the CAIF USB driver in Linux allows local users to gain kernel privileges via network namespace teardown. The cfusbl_device_notify() callback processes repeated NETDEV_UNREGISTER notifications, permitting the parent net_device to be freed before a later callback dereferences it. Exploitation requires CAP_NET_ADMIN in a user namespace and CAIF support; controlled heap reuse can disclose or modify kernel memory, while the demonstrated path can panic the kernel.
The record
- CVE
- CVE-2023-53138
- Published
- May 2, 2025
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 2, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=3.3
- Affected versionversion=7ad65bf68d705b445ef10b77ab50dab22be185ee <1793da97a23e31c5bf06631f3f3e5a25f368fd64
- Affected versionversion=7ad65bf68d705b445ef10b77ab50dab22be185ee <287027d8a567168a5d8ce5cb0cba16a34791a48c
- Affected versionversion=7ad65bf68d705b445ef10b77ab50dab22be185ee <3f14457e1584224f4296af613bbd99deb60b5d91
- Affected versionversion=7ad65bf68d705b445ef10b77ab50dab22be185ee <68a45c3cf0e2242a533657f4f535d9b6a7447a79
- Affected versionversion=7ad65bf68d705b445ef10b77ab50dab22be185ee <9781e98a97110f5e76999058368b4be76a788484
- Affected versionversion=7ad65bf68d705b445ef10b77ab50dab22be185ee <9dc16be373b382ddd4c274052a6e870a95e76c01
- Affected versionversion=7ad65bf68d705b445ef10b77ab50dab22be185ee <c3aaec463a632cf4187dc017e421bfa69d7834a9
- Affected versionversion=7ad65bf68d705b445ef10b77ab50dab22be185ee <d1a11bbdbb5ea9f172019c5a4a3e9d8eabd72179
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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