KernelScan.io

HIGH Introduced in 3.2

ath6kl AggrTimer UAF

CVE-2026-68198

CVSS 8.8 / 10.0 NVD

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

KernelScan AI7.0HIGH

01

In the Linux kernel, the following vulnerability has been resolved: wifi: ath6kl: fix use-after-free in aggr_reset_state() The aggr_reset_state() function uses timer_delete() (non-synchronous) for the aggregation timer before proceeding to delete TID state and before the structure is freed by callers like aggr_module_destroy(). If the timer callback (aggr_timeout) is executing when aggr_reset_state() is called, the callback will continue to access aggr_conn fields like rx_tid[] and stat[] which may be freed immediately after by kfree(aggr_info->aggr_conn) in aggr_module_destroy(). Additionally, the timer callback can re-arm itself via mod_timer() while aggr_reset_state() is running, creating a more complex race condition. Use timer_delete_sync() instead to ensure any running timer callback has completed before returning.

02

Engine v0.6.0

Risk summary

A local user on a system with an ath6kl WiFi adapter can trigger a use-after-free during aggregation timer teardown. The race condition between the timer callback and cleanup path can lead to kernel memory corruption, potentially enabling privilege escalation or denial of service. Exploitation requires specific Atheros AR6003/AR6004 WiFi hardware and winning a timing window.

Affecteddrivers/net/wireless/ath/ath6kl/txrx.c (ath6kl WiFi driver)

Vulnerability analysis

The WiFi driver's aggregation cleanup path deletes a timer without waiting for any in-progress callback to finish, then immediately frees the connection state that the callback accesses. If the timer fires concurrently with teardown, the callback dereferences freed memory and can even re-arm itself, widening the race window. The fix replaces the non-synchronous timer deletion with a synchronous one, guaranteeing the callback has fully exited before the caller proceeds to free the structure. This race is reachable locally by any user who can trigger WiFi connection or interface teardown on a system with the affected adapter; the timing-dependent nature of the bug makes exploitation difficult but the memory corruption primitive is unconstrained.

03

BranchIntroducedFixed inPatch commit
5.103.25.10.266a1bac650b2d6
5.153.25.15.2172132a6db0584
6.13.26.1.18417ff29cd8dbc
6.123.26.12.103b5d618fd61b9
6.183.26.18.4218965470d41e
6.63.26.6.15164af6534a085
7.13.27.1.6a3313111b5d9
mainline3.27.2ba7debb4dd64
cip/4.193.24.19.325-cip136a50212b00ffb
cip/4.19-rt3.24.19.325-cip136-rt50a50212b00ffb
cip/4.43.24.4.302-cip1158f5a9417e836
cip/4.4-rt3.24.4.302-cip115-rt638f5a9417e836
cip/5.103.25.10.268-cip77a1bac650b2d6
cip/5.10-rt3.25.10.268-cip77-rt34a1bac650b2d6
cip/6.13.26.1.187-cip6017ff29cd8dbc
cip/6.1-rt3.26.1.189-cip61-rt3217ff29cd8dbc
cip/6.123.26.12.104-cip30b5d618fd61b9

04

State of the newest release of each Civil Infrastructure Platform SLTS tree, from CIP's own fix records.

CIP treeState
cip/6.12Fixed in 6.12.104-cip30
cip/6.1Fixed in 6.1.187-cip60
cip/6.1-rtFixed in 6.1.189-cip61-rt32
cip/5.10Fixed in 5.10.268-cip77
cip/5.10-rtFixed in 5.10.268-cip77-rt34
cip/4.19Fixed in 4.19.325-cip136
cip/4.19-rtFixed in 4.19.325-cip136-rt50
cip/4.4Fixed in 4.4.302-cip115
cip/4.4-rtFixed in 4.4.302-cip115-rt63