cbcvebase.
CVE-2025-40039
published 2025-10-28

CVE-2025-40039: In the Linux kernel, the following vulnerability has been resolved: ksmbd: Fix race condition in RPC handle list access The 'sess->rpc_handle_list' XArray…

PriorityP420medium4.7CVSS 3.1
AVLACHPRLUINSUCNINAH
EPSS
0.30%
22.4th percentile
In the Linux kernel, the following vulnerability has been resolved: ksmbd: Fix race condition in RPC handle list access The 'sess->rpc_handle_list' XArray manages RPC handles within a ksmbd session. Access to this list is intended to be protected by 'sess->rpc_lock' (an rw_semaphore). However, the locking implementation was flawed, leading to potential race conditions. In ksmbd_session_rpc_open(), the code incorrectly acquired only a read lock before calling xa_store() and xa_erase(). Since these operations modify the XArray structure, a write lock is required to ensure exclusive access and prevent data corruption from concurrent modifications. Furthermore, ksmbd_session_rpc_method() accessed the list using xa_load() without holding any lock at all. This could lead to reading inconsistent data or a potential use-after-free if an entry is concurrently removed and the pointer is dereferenced. Fix these issues by: 1. Using down_write() and up_write() in ksmbd_session_rpc_open() to ensure exclusive access during XArray modification, and ensuring the lock is correctly released on error paths. 2. Adding down_read() and up_read() in ksmbd_session_rpc_method() to safely protect the lookup.

Affected

49 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.162-1 (bookworm)linux 6.1.162-1 (bookworm)
debianlinux-6.1< linux 6.1.162-1 (bookworm)linux 6.1.162-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux
linuxlinux>= 5.15.145 < 5.165.16
linuxlinux>= a4348710a7267705b75692dc1a000920481d1d92 < 69674b029002b1d90b655f014bdf64f404efa54d69674b029002b1d90b655f014bdf64f404efa54d
linuxlinux>= b685757c7b08d5073046fb379be965fd6c06aafc < 6b615a8fb3af0baf8126cde3d4fee97d57222ffc6b615a8fb3af0baf8126cde3d4fee97d57222ffc
linuxlinux>= b685757c7b08d5073046fb379be965fd6c06aafc < 5cc679ba0f4505936124cd4179ba66bb0a4bd9f35cc679ba0f4505936124cd4179ba66bb0a4bd9f3
linuxlinux>= b685757c7b08d5073046fb379be965fd6c06aafc < 6bd7e0e55dcea2cf0d391bbc21c2eb069b4be3e16bd7e0e55dcea2cf0d391bbc21c2eb069b4be3e1
linuxlinux>= b685757c7b08d5073046fb379be965fd6c06aafc < 305853cce379407090a73b38c5de5ba748893aee305853cce379407090a73b38c5de5ba748893aee
linuxlinux_kernel>= 0 < 6.1.162-16.1.162-1
linuxlinux_kernel>= 0 < 6.12.57-16.12.57-1
linuxlinux_kernel>= 0 < 6.17.6-16.17.6-1
linuxlinux_kernel>= 0 < 6.17.0-14.146.17.0-14.14
linuxlinux_kernel>= 5.15.145 < 5.165.16
linuxlinux_kernel>= 6.1.71 < 6.26.2
linuxlinux_kernel>= 6.13 < 6.17.36.17.3
linuxlinux_kernel>= 6.3 < 6.6.1236.6.123
linuxlinux_kernel>= 6.7 < 6.12.536.12.53
msrcazl3_kernel_6.6.104.2-4_on_azure_linux_3.0
msrccbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0
ubuntulinux

CVSS provenance

nvdv3.14.7MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
osv4.7MEDIUM
vendor_ubuntu7.8HIGH
vendor_debian4.7MEDIUM
vendor_msrc4.7MEDIUM
vendor_redhat4.7MEDIUM
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