cbcvebase.
CVE-2023-53517
published 2025-10-01

CVE-2023-53517: In the Linux kernel, the following vulnerability has been resolved: tipc: do not update mtu if msg_max is too small in mtu negotiation When doing link mtu…

PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.28%
20.1th percentile
In the Linux kernel, the following vulnerability has been resolved: tipc: do not update mtu if msg_max is too small in mtu negotiation When doing link mtu negotiation, a malicious peer may send Activate msg with a very small mtu, e.g. 4 in Shuang's testing, without checking for the minimum mtu, l->mtu will be set to 4 in tipc_link_proto_rcv(), then n->links[bearer_id].mtu is set to 4294967228, which is a overflow of '4 - INT_H_SIZE - EMSG_OVERHEAD' in tipc_link_mss(). With tipc_link.mtu = 4, tipc_link_xmit() kept printing the warning: tipc: Too large msg, purging xmit list 1 5 0 40 4! tipc: Too large msg, purging xmit list 1 15 0 60 4! And with tipc_link_entry.mtu 4294967228, a huge skb was allocated in named_distribute(), and when purging it in tipc_link_xmit(), a crash was even caused: general protection fault, probably for non-canonical address 0x2100001011000dd: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 0 Comm: swapper/0 Kdump: loaded Not tainted 6.3.0.neta #19 RIP: 0010:kfree_skb_list_reason+0x7e/0x1f0 Call Trace: skb_release_data+0xf9/0x1d0 kfree_skb_reason+0x40/0x100 tipc_link_xmit+0x57a/0x740 [tipc] tipc_node_xmit+0x16c/0x5c0 [tipc] tipc_named_node_up+0x27f/0x2c0 [tipc] tipc_node_write_unlock+0x149/0x170 [tipc] tipc_rcv+0x608/0x740 [tipc] tipc_udp_recv+0xdc/0x1f0 [tipc] udp_queue_rcv_one_skb+0x33e/0x620 udp_unicast_rcv_skb.isra.72+0x75/0x90 __udp4_lib_rcv+0x56d/0xc20 ip_protocol_deliver_rcu+0x100/0x2d0 This patch fixes it by checking the new mtu against tipc_bearer_min_mtu(), and not updating mtu if it is too small.

Affected

17 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.37-1 (bookworm)linux 6.1.37-1 (bookworm)
linuxlinux
linuxlinux>= ed193ece2649c194a87a9d8470195760d367c075 < 2bd4ff4ffb92113f8acd04dbaed83269172c24b42bd4ff4ffb92113f8acd04dbaed83269172c24b4
linuxlinux>= ed193ece2649c194a87a9d8470195760d367c075 < 575e84d90a74c0b091b3417ba763ebb237aa0a8c575e84d90a74c0b091b3417ba763ebb237aa0a8c
linuxlinux>= ed193ece2649c194a87a9d8470195760d367c075 < 259683001d7e879fea4b42084fb6560dd9408a7e259683001d7e879fea4b42084fb6560dd9408a7e
linuxlinux>= ed193ece2649c194a87a9d8470195760d367c075 < 1dd7ae5e0cf5a56e513f7ab7ab9570b7496281d21dd7ae5e0cf5a56e513f7ab7ab9570b7496281d2
linuxlinux>= ed193ece2649c194a87a9d8470195760d367c075 < 56077b56cd3fb78e1c8619e29581ba25a5c55e8656077b56cd3fb78e1c8619e29581ba25a5c55e86
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.191-15.10.191-1
linuxlinux_kernel>= 0 < 6.1.37-16.1.37-1
linuxlinux_kernel>= 0 < 6.3.7-16.3.7-1
linuxlinux_kernel>= 0 < 6.3.7-16.3.7-1
linuxlinux_kernel>= 4.1 < 5.10.1815.10.181
linuxlinux_kernel>= 5.11 < 5.15.1135.15.113
linuxlinux_kernel>= 5.16 < 6.1.306.1.30
linuxlinux_kernel>= 6.2 < 6.3.46.3.4

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
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