cbcvebase.
CVE-2025-40257
published 2025-12-04

CVE-2025-40257: In the Linux kernel, the following vulnerability has been resolved: mptcp: fix a race in mptcp_pm_del_add_timer() mptcp_pm_del_add_timer() can call…

PriorityP347critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.41%
33.9th percentile
In the Linux kernel, the following vulnerability has been resolved: mptcp: fix a race in mptcp_pm_del_add_timer() mptcp_pm_del_add_timer() can call sk_stop_timer_sync(sk, &entry->add_timer) while another might have free entry already, as reported by syzbot. Add RCU protection to fix this issue. Also change confusing add_timer variable with stop_timer boolean. syzbot report: BUG: KASAN: slab-use-after-free in __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616 Read of size 4 at addr ffff8880311e4150 by task kworker/1:1/44 CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events mptcp_worker Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616 sk_stop_timer_sync+0x1b/0x90 net/core/sock.c:3631 mptcp_pm_del_add_timer+0x283/0x310 net/mptcp/pm.c:362 mptcp_incoming_options+0x1357/0x1f60 net/mptcp/options.c:1174 tcp_data_queue+0xca/0x6450 net/ipv4/tcp_input.c:5361 tcp_rcv_established+0x1335/0x2670 net/ipv4/tcp_input.c:6441 tcp_v4_do_rcv+0x98b/0xbf0 net/ipv4/tcp_ipv4.c:1931 tcp_v4_rcv+0x252a/0x2dc0 net/ipv4/tcp_ipv4.c:2374 ip_protocol_deliver_rcu+0x221/0x440 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:239 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6079 [inline] __netif_receive_skb+0x143/0x380 net/core/dev.c:6192 process_backlog+0x31e/0x900 net/core/dev.c:6544 __napi_poll+0xb6/0x540 net/core/dev.c:7594 napi_poll net/core/dev.c:7657 [inline] net_rx_action+0x5f7/0xda0 net/core/dev.c:7784 handle_softirqs+0x22f/0x710 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] __local_b

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>= 00cfd77b9063dcdf3628a7087faba60de85a9cc8 < 9be29f8e7ce4e147e56caac2c3a0ce3573cf9c179be29f8e7ce4e147e56caac2c3a0ce3573cf9c17
linuxlinux>= 00cfd77b9063dcdf3628a7087faba60de85a9cc8 < e2d1ad207174a7cd7903dd27a00db4b2dfa6c64be2d1ad207174a7cd7903dd27a00db4b2dfa6c64b
linuxlinux>= 00cfd77b9063dcdf3628a7087faba60de85a9cc8 < 385ddc0f008f24d1e7d03be998b3a98a37bd29ff385ddc0f008f24d1e7d03be998b3a98a37bd29ff
linuxlinux>= 00cfd77b9063dcdf3628a7087faba60de85a9cc8 < c602cc344b4b8d41515fec3ffa98457ac963ee12c602cc344b4b8d41515fec3ffa98457ac963ee12
linuxlinux>= 00cfd77b9063dcdf3628a7087faba60de85a9cc8 < 6d3275d4ca62e2c02e1b7e8cd32db59df91c14b76d3275d4ca62e2c02e1b7e8cd32db59df91c14b7
linuxlinux>= 00cfd77b9063dcdf3628a7087faba60de85a9cc8 < bbbd75346c8e6490b19c2ba90f38ea66ccf352b2bbbd75346c8e6490b19c2ba90f38ea66ccf352b2
linuxlinux>= 00cfd77b9063dcdf3628a7087faba60de85a9cc8 < 426358d9be7ce3518966422f87b96f1bad27295f426358d9be7ce3518966422f87b96f1bad27295f
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>= 5.10.0 < 5.10.2475.10.247
linuxlinux_kernel>= 5.11.0 < 5.15.1975.15.197
linuxlinux_kernel>= 5.16.0 < 6.1.1596.1.159
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_ubuntu7.8HIGH
vendor_redhat6.7MEDIUM
vendor_msrc6.3MEDIUM
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