cbcvebase.
CVE-2025-68341
published 2025-12-23

CVE-2025-68341: In the Linux kernel, the following vulnerability has been resolved: veth: reduce XDP no_direct return section to fix race As explain in commit fa349e396e48…

PriorityP352critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.44%
37.2th percentile
In the Linux kernel, the following vulnerability has been resolved: veth: reduce XDP no_direct return section to fix race As explain in commit fa349e396e48 ("veth: Fix race with AF_XDP exposing old or uninitialized descriptors") for veth there is a chance after napi_complete_done() that another CPU can manage start another NAPI instance running veth_pool(). For NAPI this is correctly handled as the napi_schedule_prep() check will prevent multiple instances from getting scheduled, but for the remaining code in veth_pool() this can run concurrent with the newly started NAPI instance. The problem/race is that xdp_clear_return_frame_no_direct() isn't designed to be nested. Prior to commit 401cb7dae813 ("net: Reference bpf_redirect_info via task_struct on PREEMPT_RT.") the temporary BPF net context bpf_redirect_info was stored per CPU, where this wasn't an issue. Since this commit the BPF context is stored in 'current' task_struct. When running veth in threaded-NAPI mode, then the kthread becomes the storage area. Now a race exists between two concurrent veth_pool() function calls one exiting NAPI and one running new NAPI, both using the same BPF net context. Race is when another CPU gets within the xdp_set_return_frame_no_direct() section before exiting veth_pool() calls the clear-function xdp_clear_return_frame_no_direct().

Affected

10 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.17.11-1 (forky)linux 6.17.11-1 (forky)
linuxlinux——
linuxlinux>= 401cb7dae8130fd34eb84648e02ab4c506df7d5e < c1ceabcb347d1b0f7e70a7384ec7eff3847b7628c1ceabcb347d1b0f7e70a7384ec7eff3847b7628
linuxlinux>= 401cb7dae8130fd34eb84648e02ab4c506df7d5e < d0bd018ad72a8a598ae709588934135017f8af52d0bd018ad72a8a598ae709588934135017f8af52
linuxlinux>= 401cb7dae8130fd34eb84648e02ab4c506df7d5e < a14602fcae17a3f1cb8a8521bedf31728f9e7e39a14602fcae17a3f1cb8a8521bedf31728f9e7e39
linuxlinux_kernel>= 0 < 6.12.63-16.12.63-1
linuxlinux_kernel>= 0 < 6.17.11-16.17.11-1
linuxlinux_kernel>= 0 < 6.17.0-19.196.17.0-19.19
linuxlinux_kernel>= 6.11.0 < 6.12.616.12.61
linuxlinux_kernel>= 6.13.0 < 6.17.116.17.11

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv7.2HIGH
vendor_ubuntu7.2HIGH
vendor_redhat5.5LOW
Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.