cbcvebase.
CVE-2023-23586
published 2023-02-17

CVE-2023-23586: Due to a vulnerability in the io_uring subsystem, it is possible to leak kernel memory information to the user process. timens_install calls…

PriorityP424medium5.5CVSS 3.1
AVLACLPRLUINSUCHINAN
EPSS
0.27%
19.0th percentile
Due to a vulnerability in the io_uring subsystem, it is possible to leak kernel memory information to the user process. timens_install calls current_is_single_threaded to determine if the current process is single-threaded, but this call does not consider io_uring's io_worker threads, thus it is possible to insert a time namespace's vvar page to process's memory space via a page fault. When this time namespace is destroyed, the vvar page is also freed, but not removed from the process' memory, and a next page allocated by the kernel will be still available from the user-space process and can leak memory contents via this (read-only) use-after-free vulnerability. We recommend upgrading past version 5.10.161 or commit 788d0824269bef539fe31a785b1517882eafed93 https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/io_uring

Affected

7 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.14.6-1 (bookworm)linux 5.14.6-1 (bookworm)
linuxlinux_kernel>= 0 < 5.10.162-15.10.162-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 5.6 < 5.10.1615.10.161
linuxlinux_kernel5.6 – 5.10.161

CVSS provenance

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