Local privilege escalation via ipvlan teardown race
Published Jan 19, 2025 · Updated Aug 5, 2026
Use-after-free in affected Linux kernel 6.x branches allows local users to escalate privileges through an ipvlan teardown race. When linkwatch evaluates an ipvlan device after its lower network device is freed, ipvlan_get_iflink dereferences the stale phy_dev pointer without lifetime protection. An unprivileged local user can obtain CAP_NET_ADMIN inside new user and network namespaces, race device teardown against linkwatch, and cause kernel memory corruption or a panic.
Summary
What happened
Use-after-free in affected Linux kernel 6.x branches allows local users to escalate privileges through an ipvlan teardown race. When linkwatch evaluates an ipvlan device after its lower network device is freed, ipvlan_get_iflink dereferences the stale phy_dev pointer without lifetime protection. An unprivileged local user can obtain CAP_NET_ADMIN inside new user and network namespaces, race device teardown against linkwatch, and cause kernel memory corruption or a panic.
The record
- CVE
- CVE-2025-21652
- Published
- Jan 19, 2025
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-416, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jan 19, 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=6.2
- Affected versionversion=8c55facecd7ade835287298ce325f930d888d8ec <52a24538d569f48e79d1a169a5d359d384152950
- Affected versionversion=8c55facecd7ade835287298ce325f930d888d8ec <ba9f7c16ec879c83bb4f80406773a911aace8267
- Affected versionversion=8c55facecd7ade835287298ce325f930d888d8ec <cb358ff94154774d031159b018adf45e17673941
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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Public exploit references
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Technologies
Your stack
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Your stack
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