CVE-2023-53072

HIGH EPSS 5.7%
Published May 2, 20251y ago · Modified Jun 17, 20261w ago
7.8 CVSS 3.1
High
Find Similar
Published May 2, 2025 1y ago
Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: use the workqueue to destroy unaccepted sockets Christoph reported a UaF at token lookup time after having refactored the passive socket initialization part: BUG: KASAN: use-after-free in __token_bucket_busy+0x253/0x260 Read of size 4 at addr ffff88810698d5b0 by task syz-executor653/3198 CPU: 1 PID: 3198 Comm: syz-executor653 Not tainted 6.2.0-rc59af4eaa31c1f6c00c8f1e448ed99a45c66340dd5 #6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x6e/0x91 print_report+0x16a/0x46f kasan_report+0xad/0x130 __token_bucket_busy+0x253/0x260 mptcp_token_new_connect+0x13d/0x490 mptcp_connect+0x4ed/0x860 __inet_stream_connect+0x80e/0xd90 tcp_sendmsg_fastopen+0x3ce/0x710 mptcp_sendmsg+0xff1/0x1a20 inet_sendmsg+0x11d/0x140 __sys_sendto+0x405/0x490 __x64_sys_sendto+0xdc/0x1b0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc We need to properly clean-up all the paired MPTCP-level resources and be sure to release the msk last, even when the unaccepted subflow is destroyed by the TCP internals via inet_child_forget(). We can re-use the existing MPTCP_WORK_CLOSE_SUBFLOW infra, explicitly checking that for the critical scenario: the closed subflow is the MPC one, the msk is not accepted and eventually going through full cleanup. With such change, __mptcp_destroy_sock() is always called on msk sockets, even on accepted ones. We don't need anymore to transiently drop one sk reference at msk clone time. Please note this commit depends on the parent one: mptcp: refactor passive socket initialization

CVSS Details

Base Score
7.8
Exploitability
1.8
Impact
5.9
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
5.7% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-416 Use After Free Memory Safety

Affected Products 4

VendorProductVersionRange
linuxlinux_kernel*≥5.7  –  <6.1.22
linuxlinux_kernel*≥6.2  –  <6.2.8
linuxlinux_kernel6.3any
linuxlinux_kernel6.3any

References 3

  • git.kernel.org https://git.kernel.org/stable/c/2827f099b3fb9a59263c997400e9182f5d423e84
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/804cf487fb0031f3c74755b78d8663333f0ba636
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b6985b9b82954caa53f862d6059d06c0526254f0
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/2827f099b3fb9a59263c997400e9182f5d423e84
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/804cf487fb0031f3c74755b78d8663333f0ba636
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b6985b9b82954caa53f862d6059d06c0526254f0
    Patch