cbcvebase.
CVE-2025-21653
published 2025-01-19

CVE-2025-21653: In the Linux kernel, the following vulnerability has been resolved: net_sched: cls_flow: validate TCA_FLOW_RSHIFT attribute syzbot found that TCA_FLOW_RSHIFT…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.21%
11.5th percentile
In the Linux kernel, the following vulnerability has been resolved: net_sched: cls_flow: validate TCA_FLOW_RSHIFT attribute syzbot found that TCA_FLOW_RSHIFT attribute was not validated. Right shitfing a 32bit integer is undefined for large shift values. UBSAN: shift-out-of-bounds in net/sched/cls_flow.c:329:23 shift exponent 9445 is too large for 32-bit type 'u32' (aka 'unsigned int') CPU: 1 UID: 0 PID: 54 Comm: kworker/u8:3 Not tainted 6.13.0-rc3-syzkaller-00180-g4f619d518db9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:231 [inline] __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468 flow_classify+0x24d5/0x25b0 net/sched/cls_flow.c:329 tc_classify include/net/tc_wrapper.h:197 [inline] __tcf_classify net/sched/cls_api.c:1771 [inline] tcf_classify+0x420/0x1160 net/sched/cls_api.c:1867 sfb_classify net/sched/sch_sfb.c:260 [inline] sfb_enqueue+0x3ad/0x18b0 net/sched/sch_sfb.c:318 dev_qdisc_enqueue+0x4b/0x290 net/core/dev.c:3793 __dev_xmit_skb net/core/dev.c:3889 [inline] __dev_queue_xmit+0xf0e/0x3f50 net/core/dev.c:4400 dev_queue_xmit include/linux/netdevice.h:3168 [inline] neigh_hh_output include/net/neighbour.h:523 [inline] neigh_output include/net/neighbour.h:537 [inline] ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:236 iptunnel_xmit+0x55d/0x9b0 net/ipv4/ip_tunnel_core.c:82 udp_tunnel_xmit_skb+0x262/0x3b0 net/ipv4/udp_tunnel_core.c:173 geneve_xmit_skb drivers/net/geneve.c:916 [inline] geneve_xmit+0x21dc/0x2d00 drivers/net/geneve.c:1039 __netdev_start_xmit include/linux/netdevice.h:5002 [inline] netdev_start_xmit include/linux/netdevice.h:5011 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x27a/0x7d0 net/core/dev.c:3606 __dev_queue_xmit+0x1b73/0x3f50 net/core/dev.c:4434

Affected

24 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.128-1 (bookworm)linux 6.1.128-1 (bookworm)
debianlinux-6.1< linux 6.1.128-1 (bookworm)linux 6.1.128-1 (bookworm)
linuxlinux
linuxlinux>= e5dfb815181fcb186d6080ac3a091eadff2d98fe < 9858f4afeb2e59506e714176bd3e135539a3eeec9858f4afeb2e59506e714176bd3e135539a3eeec
linuxlinux>= e5dfb815181fcb186d6080ac3a091eadff2d98fe < 43658e4a5f2770ad94e93362885ff51c10cf317943658e4a5f2770ad94e93362885ff51c10cf3179
linuxlinux>= e5dfb815181fcb186d6080ac3a091eadff2d98fe < a313d6e6d5f3a631cae5a241c392c28868aa5c5ea313d6e6d5f3a631cae5a241c392c28868aa5c5e
linuxlinux>= e5dfb815181fcb186d6080ac3a091eadff2d98fe < 2011749ca96460386844dfc7e0fde53ebee96f3c2011749ca96460386844dfc7e0fde53ebee96f3c
linuxlinux>= e5dfb815181fcb186d6080ac3a091eadff2d98fe < e54beb9aed2a90dddf4c5d68fcfc9a01f3e40a61e54beb9aed2a90dddf4c5d68fcfc9a01f3e40a61
linuxlinux>= e5dfb815181fcb186d6080ac3a091eadff2d98fe < 6fde663f7321418996645ee602a473457640542f6fde663f7321418996645ee602a473457640542f
linuxlinux>= e5dfb815181fcb186d6080ac3a091eadff2d98fe < a039e54397c6a75b713b9ce7894a62e06956aa92a039e54397c6a75b713b9ce7894a62e06956aa92
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.234-15.10.234-1
linuxlinux_kernel>= 0 < 6.1.128-16.1.128-1
linuxlinux_kernel>= 0 < 6.12.10-16.12.10-1
linuxlinux_kernel>= 0 < 6.12.10-16.12.10-1
linuxlinux_kernel>= 0 < 5.4.0-211.2315.4.0-211.231
linuxlinux_kernel>= 0 < 5.15.0-135.1465.15.0-135.146
linuxlinux_kernel>= 0 < 6.8.0-60.636.8.0-60.63
linuxlinux_kernel>= 2.6.25 < 5.4.2905.4.290
linuxlinux_kernel>= 5.11 < 5.15.1775.15.177
linuxlinux_kernel>= 5.16 < 6.1.1256.1.125
linuxlinux_kernel>= 5.5 < 5.10.2345.10.234
linuxlinux_kernel>= 6.2 < 6.6.726.6.72
linuxlinux_kernel>= 6.7 < 6.12.106.12.10

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv7.8HIGH
vendor_ubuntu7.8HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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