Race condition in Linux kernel - CVE-2026-68138
Published: August 12, 2026
Vulnerability identifier: #VU142170
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-68138
CWE-ID: CWE-362
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a race condition leading to use-after-free and double-free in qdisc_get_rtab() and qdisc_put_rtab() when processing concurrent RTM_NEWTFILTER requests that add flower filters with a police action carrying the same rate. A local user can send concurrent netlink filter configuration requests to cause a denial of service.
The corrupted qdisc_rate_table object is shared system-wide because the affected rate-table list is process-global rather than per-network-namespace.
Affected software
Linux kernel
Debian Linux
linux (Debian package)
Debian Linux
linux (Debian package)
How to mitigate CVE-2026-68138
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
linux (Debian package) - update to 6.12.105-1
linux (Debian package) - update to 6.12.105-1