CVE-2026-89854high

CVE-2026-89854: high-severity vulnerability in Linux

scsi: qla2xxx: Fix cs84xx use-after-free on host teardown

Published

21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.8epss 0.2%
exploitation probability
0.2%top 94% of all CVEs
observed exploitation
nono source reports it
In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Fix cs84xx use-after-free on host teardown qla84xx_put_chip() drops the last reference to ha->cs84xx and frees it via __qla84xx_chip_release() without clearing ha->cs84xx. During teardown it ran before scsi_remove_host(), which is what removes the 84xx_fw_version host sysfs attribute. A concurrent read of that attribute in the window between the two calls executes qla24xx_84xx_fw_version_show(), which dereferences the freed ha->cs84xx, resulting in a use-after-free. Move qla84xx_put_chip() to after scsi_remove_host() in both qla2x00_remove_one() and qla2x00_disable_board_on_pci_error(). Once scsi_remove_host() returns, the sysfs attribute is gone and kernfs has drained any in-flight show(), so no reader can touch cs84xx; the put still runs before the host and ha are freed.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products
Linux · Linux