Description
In the Linux kernel, the following vulnerability has been resolved:
media: em28xx: fix use-after-free of dev_next->devlist on disconnect
When a device with has_dual_ts=1 is probed and the is_audio_only path
is taken, both dev and dev->dev_next are added to the global
em28xx_devlist via em28xx_init_extension(). However, during disconnect,
em28xx_close_extension(dev) only calls list_del(&dev->devlist), leaving
dev->dev_next->devlist still linked in the global list. When dev_next is
subsequently freed via kref_put(), its devlist entry becomes a dangling
pointer in em28xx_devlist. The next device probe that calls
em28xx_init_extension() triggers a list corruption BUG when list_add_tail
detects the freed node.
This bug was exposed by commit a368ecde8a50 ("USB: core: Fix duplicate
endpoint bug by clearing reserved bits in the descriptor") which clears
reserved bits in bEndpointAddress during endpoint parsing. This causes
fuzzed endpoint addresses like 0xf3 to be normalized to 0x83, which
em28xx interprets as a vendor audio endpoint, enabling the
is_audio_only + has_dual_ts code path that was previously unreachable
with such descriptors.
Fix this by removing dev->dev_next->devlist from the global list in
em28xx_close_extension() before the device is freed.
media: em28xx: fix use-after-free of dev_next->devlist on disconnect
When a device with has_dual_ts=1 is probed and the is_audio_only path
is taken, both dev and dev->dev_next are added to the global
em28xx_devlist via em28xx_init_extension(). However, during disconnect,
em28xx_close_extension(dev) only calls list_del(&dev->devlist), leaving
dev->dev_next->devlist still linked in the global list. When dev_next is
subsequently freed via kref_put(), its devlist entry becomes a dangling
pointer in em28xx_devlist. The next device probe that calls
em28xx_init_extension() triggers a list corruption BUG when list_add_tail
detects the freed node.
This bug was exposed by commit a368ecde8a50 ("USB: core: Fix duplicate
endpoint bug by clearing reserved bits in the descriptor") which clears
reserved bits in bEndpointAddress during endpoint parsing. This causes
fuzzed endpoint addresses like 0xf3 to be normalized to 0x83, which
em28xx interprets as a vendor audio endpoint, enabling the
is_audio_only + has_dual_ts code path that was previously unreachable
with such descriptors.
Fix this by removing dev->dev_next->devlist from the global list in
em28xx_close_extension() before the device is freed.
Published:
2026-09-16
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
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Remediation
No vendor fix or workaround currently provided.
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Tracking
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Advisories
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References
History
Wed, 16 Sep 2026 10:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: media: em28xx: fix use-after-free of dev_next->devlist on disconnect When a device with has_dual_ts=1 is probed and the is_audio_only path is taken, both dev and dev->dev_next are added to the global em28xx_devlist via em28xx_init_extension(). However, during disconnect, em28xx_close_extension(dev) only calls list_del(&dev->devlist), leaving dev->dev_next->devlist still linked in the global list. When dev_next is subsequently freed via kref_put(), its devlist entry becomes a dangling pointer in em28xx_devlist. The next device probe that calls em28xx_init_extension() triggers a list corruption BUG when list_add_tail detects the freed node. This bug was exposed by commit a368ecde8a50 ("USB: core: Fix duplicate endpoint bug by clearing reserved bits in the descriptor") which clears reserved bits in bEndpointAddress during endpoint parsing. This causes fuzzed endpoint addresses like 0xf3 to be normalized to 0x83, which em28xx interprets as a vendor audio endpoint, enabling the is_audio_only + has_dual_ts code path that was previously unreachable with such descriptors. Fix this by removing dev->dev_next->devlist from the global list in em28xx_close_extension() before the device is freed. | |
| Title | media: em28xx: fix use-after-free of dev_next->devlist on disconnect | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-16T10:31:53.963Z
Reserved: 2026-09-11T19:38:34.773Z
Link: CVE-2026-89891
No data.
Status : Received
Published: 2026-09-16T11:16:57.740
Modified: 2026-09-16T11:16:57.740
Link: CVE-2026-89891
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.
