Kernel crash via dangling em28xx device-list entry
Published Sep 16, 2026 · Updated Sep 16, 2026
Use-after-free in the Linux em28xx USB media driver allows physically proximate attackers to crash the kernel using crafted USB descriptors. On disconnect, em28xx_close_extension() unlinks only the primary device before kref_put() frees dev_next, leaving dev_next->devlist in em28xx_devlist. A dual-transport-stream device must enter the audio-only probe path and then be disconnected; a later em28xx probe detects list corruption and triggers a kernel BUG.
Summary
What happened
Use-after-free in the Linux em28xx USB media driver allows physically proximate attackers to crash the kernel using crafted USB descriptors. On disconnect, em28xx_close_extension() unlinks only the primary device before kref_put() frees dev_next, leaving dev_next->devlist in em28xx_devlist. A dual-transport-stream device must enter the audio-only probe path and then be disconnected; a later em28xx probe detects list corruption and triggers a kernel BUG.
The record
- CVE
- CVE-2026-89891
- Published
- Sep 16, 2026
- Updated
- Sep 16, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499
- Attack vector
- physical
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 16, 2026CVE publishedPublication date reported by the CVE source.
- Sep 16, 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=4.17
- Affected versionversion=f410b4093fdd4d8f4644d3d486afe3040eceef7b <0782807552b6aff41b4656c6c9076a3231d3e79d
- Affected versionversion=f410b4093fdd4d8f4644d3d486afe3040eceef7b <16cb1ee17e093175b4d9ae33202f68e5b108cca2
- Affected versionversion=f410b4093fdd4d8f4644d3d486afe3040eceef7b <1ed575b1991f68569eb589b7747d3bc26aa6a8a2
- Affected versionversion=f410b4093fdd4d8f4644d3d486afe3040eceef7b <20aacd87550be297dc39a3f9532dcfff91586510
- Affected versionversion=f410b4093fdd4d8f4644d3d486afe3040eceef7b <20c2c65f3d9f7c278dc9750531d3201ac8bf78b7
- Affected versionversion=f410b4093fdd4d8f4644d3d486afe3040eceef7b <826915b6b65e2d3251e7248ea54289a22d748c84
- Affected versionversion=f410b4093fdd4d8f4644d3d486afe3040eceef7b <da4b07da6281e39ce4c01e1227e036f3bf600e14
- Affected versionversion=f410b4093fdd4d8f4644d3d486afe3040eceef7b <f61720346fdcc1a2deec59a2f6cbb0cc20d1dc18
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- syzbot C reproducer for em28xx use-after-freefunctional · validated
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Technologies
Your stack
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Your stack
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