cbcvebase.
CVE-2025-21706
published 2025-02-27

CVE-2025-21706: In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: only set fullmesh for subflow endp With the in-kernel path-manager, it is…

PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.21%
10.7th percentile
In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: only set fullmesh for subflow endp With the in-kernel path-manager, it is possible to change the 'fullmesh' flag. The code in mptcp_pm_nl_fullmesh() expects to change it only on 'subflow' endpoints, to recreate more or less subflows using the linked address. Unfortunately, the set_flags() hook was a bit more permissive, and allowed 'implicit' endpoints to get the 'fullmesh' flag while it is not allowed before. That's what syzbot found, triggering the following warning: WARNING: CPU: 0 PID: 6499 at net/mptcp/pm_netlink.c:1496 __mark_subflow_endp_available net/mptcp/pm_netlink.c:1496 [inline] WARNING: CPU: 0 PID: 6499 at net/mptcp/pm_netlink.c:1496 mptcp_pm_nl_fullmesh net/mptcp/pm_netlink.c:1980 [inline] WARNING: CPU: 0 PID: 6499 at net/mptcp/pm_netlink.c:1496 mptcp_nl_set_flags net/mptcp/pm_netlink.c:2003 [inline] WARNING: CPU: 0 PID: 6499 at net/mptcp/pm_netlink.c:1496 mptcp_pm_nl_set_flags+0x974/0xdc0 net/mptcp/pm_netlink.c:2064 Modules linked in: CPU: 0 UID: 0 PID: 6499 Comm: syz.1.413 Not tainted 6.13.0-rc5-syzkaller-00172-gd1bf27c4e176 #0 Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__mark_subflow_endp_available net/mptcp/pm_netlink.c:1496 [inline] RIP: 0010:mptcp_pm_nl_fullmesh net/mptcp/pm_netlink.c:1980 [inline] RIP: 0010:mptcp_nl_set_flags net/mptcp/pm_netlink.c:2003 [inline] RIP: 0010:mptcp_pm_nl_set_flags+0x974/0xdc0 net/mptcp/pm_netlink.c:2064 Code: 01 00 00 49 89 c5 e8 fb 45 e8 f5 e9 b8 fc ff ff e8 f1 45 e8 f5 4c 89 f7 be 03 00 00 00 e8 44 1d 0b f9 eb a0 e8 dd 45 e8 f5 90 0b 90 e9 17 ff ff ff 89 d9 80 e1 07 38 c1 0f 8c c9 fc ff ff 48 RSP: 0018:ffffc9000d307240 EFLAGS: 00010293 RAX: ffffffff8bb72e03 RBX: 0000000000000000 RCX: ffff88807da88000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000d307430 R08: ffffffff8bb72cf0 R09: 1ffff1100b842a5e R10: dffffc0000000000 R11: ffffed100b842a5f R12: ffff

Affected

16 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.129-1 (bookworm)linux 6.1.129-1 (bookworm)
debianlinux-6.1< linux 6.1.129-1 (bookworm)linux 6.1.129-1 (bookworm)
linuxlinux
linuxlinux>= 73c762c1f07dacba4fd1cefd15e24b419d42320d < 22b0734c9401a74ed4ebd9e8ef0da33e493852eb22b0734c9401a74ed4ebd9e8ef0da33e493852eb
linuxlinux>= 73c762c1f07dacba4fd1cefd15e24b419d42320d < de3b8d41d2547452c4cafb146d003fa4689fbaf2de3b8d41d2547452c4cafb146d003fa4689fbaf2
linuxlinux>= 73c762c1f07dacba4fd1cefd15e24b419d42320d < 8ac344cbd84fda75e05e1f445f7f8fb24dc175e18ac344cbd84fda75e05e1f445f7f8fb24dc175e1
linuxlinux>= 73c762c1f07dacba4fd1cefd15e24b419d42320d < 9e3d61620a3cd033319553b980ff3a350adbe1bc9e3d61620a3cd033319553b980ff3a350adbe1bc
linuxlinux>= 73c762c1f07dacba4fd1cefd15e24b419d42320d < 1bb0d1348546ad059f55c93def34e67cb2a034a61bb0d1348546ad059f55c93def34e67cb2a034a6
linuxlinux_kernel>= 0 < 6.1.129-16.1.129-1
linuxlinux_kernel>= 0 < 6.12.13-16.12.13-1
linuxlinux_kernel>= 0 < 6.12.13-16.12.13-1
linuxlinux_kernel>= 0 < 6.8.0-78.786.8.0-78.78
linuxlinux_kernel>= 5.18 < 6.1.1296.1.129
linuxlinux_kernel>= 6.13 < 6.13.26.13.2
linuxlinux_kernel>= 6.2 < 6.6.786.6.78
linuxlinux_kernel>= 6.7 < 6.12.136.12.13

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
vendor_ubuntu5.5MEDIUM
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