cbcvebase.
CVE-2026-23009
published 2026-01-25

CVE-2026-23009: In the Linux kernel, the following vulnerability has been resolved: xhci: sideband: don't dereference freed ring when removing sideband endpoint…

PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.14%
3.4th percentile
In the Linux kernel, the following vulnerability has been resolved: xhci: sideband: don't dereference freed ring when removing sideband endpoint xhci_sideband_remove_endpoint() incorrecly assumes that the endpoint is running and has a valid transfer ring. Lianqin reported a crash during suspend/wake-up stress testing, and found the cause to be dereferencing a non-existing transfer ring 'ep->ring' during xhci_sideband_remove_endpoint(). The endpoint and its ring may be in unknown state if this function is called after xHCI was reinitialized in resume (lost power), or if device is being re-enumerated, disconnected or endpoint already dropped. Fix this by both removing unnecessary ring access, and by checking ep->ring exists before dereferencing it. Also make sure endpoint is running before attempting to stop it. Remove the xhci_initialize_ring_info() call during sideband endpoint removal as is it only initializes ring structure enqueue, dequeue and cycle state values to their starting values without changing actual hardware enqueue, dequeue and cycle state. Leaving them out of sync is worse than leaving it as it is. The endpoint will get freed in after this in most usecases. If the (audio) class driver want's to reuse the endpoint after offload then it is up to the class driver to ensure endpoint is properly set up.

Affected

15 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.18.8-1 (forky)linux 6.18.8-1 (forky)
linuxlinux
linuxlinux>= de66754e9f8029f8ae955a588959b99cab56b506 < 34f6634dba87ef72b3c3a3a524be663adef7ab4234f6634dba87ef72b3c3a3a524be663adef7ab42
linuxlinux>= de66754e9f8029f8ae955a588959b99cab56b506 < dd83dc1249737b837ac5d57c81f2b0977c613d9fdd83dc1249737b837ac5d57c81f2b0977c613d9f
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.18.8-16.18.8-1
linuxlinux_kernel>= 6.16.0 < 6.18.76.18.7
linuxlinux_kernel>= 6.16.1 < 6.18.76.18.7
ubuntulinux-azure-6.17
ubuntulinux-azure-fde-6.17
ubuntulinux-gcp-6.17
ubuntulinux-oem-6.17
ubuntulinux-oracle-6.17
ubuntulinux-realtime-6.17

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5LOW
vendor_redhat5.5MEDIUM
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