cbcvebase.
CVE-2025-40258
published 2025-12-04

CVE-2025-40258: In the Linux kernel, the following vulnerability has been resolved: mptcp: fix race condition in mptcp_schedule_work() syzbot reported use-after-free in…

PriorityP346critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.41%
33.9th percentile
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix race condition in mptcp_schedule_work() syzbot reported use-after-free in mptcp_schedule_work() [1] Issue here is that mptcp_schedule_work() schedules a work, then gets a refcount on sk->sk_refcnt if the work was scheduled. This refcount will be released by mptcp_worker(). [A] if (schedule_work(...)) { [B] sock_hold(sk); return true; } Problem is that mptcp_worker() can run immediately and complete before [B] We need instead : sock_hold(sk); if (schedule_work(...)) return true; sock_put(sk); [1] refcount_t: addition on 0; use-after-free. WARNING: CPU: 1 PID: 29 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25 Call Trace: __refcount_add include/linux/refcount.h:-1 [inline] __refcount_inc include/linux/refcount.h:366 [inline] refcount_inc include/linux/refcount.h:383 [inline] sock_hold include/net/sock.h:816 [inline] mptcp_schedule_work+0x164/0x1a0 net/mptcp/protocol.c:943 mptcp_tout_timer+0x21/0xa0 net/mptcp/protocol.c:2316 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x648/0x970 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x22f/0x710 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] run_ktimerd+0xcf/0x190 kernel/softirq.c:1138 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Affected

27 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.159-1 (bookworm)linux 6.1.159-1 (bookworm)
debianlinux-6.1< linux 6.1.159-1 (bookworm)linux 6.1.159-1 (bookworm)
linuxlinux
linuxlinux>= 3b1d6210a9577369103330b0d802b0bf74b65e7f < f865e6595acf33083168db76921e66ace8bf0e5bf865e6595acf33083168db76921e66ace8bf0e5b
linuxlinux>= 3b1d6210a9577369103330b0d802b0bf74b65e7f < 99908e2d601236842d705d5fd04fb349577316f599908e2d601236842d705d5fd04fb349577316f5
linuxlinux>= 3b1d6210a9577369103330b0d802b0bf74b65e7f < db4f7968a75250ca6c4ed70d0a78beabb2dcee18db4f7968a75250ca6c4ed70d0a78beabb2dcee18
linuxlinux>= 3b1d6210a9577369103330b0d802b0bf74b65e7f < 8f9ba1a99a89feef9b5867c15a0141a97e8933098f9ba1a99a89feef9b5867c15a0141a97e893309
linuxlinux>= 3b1d6210a9577369103330b0d802b0bf74b65e7f < ac28dfddedf6f209190950fc71bcff65ec4ab47bac28dfddedf6f209190950fc71bcff65ec4ab47b
linuxlinux>= 3b1d6210a9577369103330b0d802b0bf74b65e7f < 3fc7723ed01d1130d4bf7063c50e0af60ecccbb43fc7723ed01d1130d4bf7063c50e0af60ecccbb4
linuxlinux>= 3b1d6210a9577369103330b0d802b0bf74b65e7f < 035bca3f017ee9dea3a5a756e77a6f7138cc6eea035bca3f017ee9dea3a5a756e77a6f7138cc6eea
linuxlinux_kernel>= 0 < 5.10.247-15.10.247-1
linuxlinux_kernel>= 0 < 6.1.159-16.1.159-1
linuxlinux_kernel>= 0 < 6.12.63-16.12.63-1
linuxlinux_kernel>= 0 < 6.17.10-16.17.10-1
linuxlinux_kernel>= 0 < 5.15.0-173.1835.15.0-173.183
linuxlinux_kernel>= 0 < 6.8.0-106.1066.8.0-106.106
linuxlinux_kernel>= 0 < 6.17.0-19.196.17.0-19.19
linuxlinux_kernel>= 5.11.0 < 5.15.1975.15.197
linuxlinux_kernel>= 5.16.0 < 6.1.1596.1.159
linuxlinux_kernel>= 5.7.0 < 5.10.2475.10.247
linuxlinux_kernel>= 6.13.0 < 6.17.106.17.10
linuxlinux_kernel>= 6.2.0 < 6.6.1186.6.118
linuxlinux_kernel>= 6.7.0 < 6.12.606.12.60
msrcazl3_kernel_6.6.112.1-2_on_azure_linux_3.0
msrcazl3_kernel_6.6.117.1-1_on_azure_linux_3.0

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_redhat7.8MEDIUM
vendor_ubuntu7.8HIGH
vendor_msrc7.0HIGH
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