CVE-2026-43203

HIGH

atm: fore200e: fix use-after-free in tasklets during device removal

Title source: cna
STIX 2.1

Description

In the Linux kernel, the following vulnerability has been resolved: atm: fore200e: fix use-after-free in tasklets during device removal When the PCA-200E or SBA-200E adapter is being detached, the fore200e is deallocated. However, the tx_tasklet or rx_tasklet may still be running or pending, leading to use-after-free bug when the already freed fore200e is accessed again in fore200e_tx_tasklet() or fore200e_rx_tasklet(). One of the race conditions can occur as follows: CPU 0 (cleanup) | CPU 1 (tasklet) fore200e_pca_remove_one() | fore200e_interrupt() fore200e_shutdown() | tasklet_schedule() kfree(fore200e) | fore200e_tx_tasklet() | fore200e-> // UAF Fix this by ensuring tx_tasklet or rx_tasklet is properly canceled before the fore200e is released. Add tasklet_kill() in fore200e_shutdown() to synchronize with any pending or running tasklets. Moreover, since fore200e_reset() could prevent further interrupts or data transfers, the tasklet_kill() should be placed after fore200e_reset() to prevent the tasklet from being rescheduled in fore200e_interrupt(). Finally, it only needs to do tasklet_kill() when the fore200e state is greater than or equal to FORE200E_STATE_IRQ, since tasklets are uninitialized in earlier states. In a word, the tasklet_kill() should be placed in the FORE200E_STATE_IRQ branch within the switch...case structure. This bug was identified through static analysis.

Scores

CVSS v3 7.5
EPSS 0.0043
EPSS Percentile 35.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Details

CWE
CWE-416
Status published
Products (27)
linux/Kernel 2.6.12 - 5.10.252linux
linux/Kernel 5.11.0 - 5.15.202linux
linux/Kernel 5.16.0 - 6.1.165linux
linux/Kernel 6.13.0 - 6.18.16linux
linux/Kernel 6.19.0 - 6.19.6linux
linux/Kernel 6.2.0 - 6.6.128linux
linux/Kernel 6.7.0 - 6.12.75linux
Linux/Linux < 2.6.12
Linux/Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 - 5189368f10903956be05062d160b2804bf5e5016
Linux/Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 - 73fbc5d1a9ccb626937500bbd67136f077d8237b
... and 17 more
Published May 06, 2026
Tracked Since May 06, 2026