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 current_is_single_threaded to determine if the current process is single-threaded, but this call does not…
Does this matter?
Lower severity and a low EPSS score (0.27%). Track it; it rarely justifies an emergency change on its own.
Description
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
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 0.27% probability · 19th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-416
- Affected
- linux/linux kernel
- Source
- cve-coordination@google.com
References
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/io_uring?h=linux-5.10.y&id=788d0824269bef539fe31a785b1517882eafed93Mailing List, Patch
- https://kernel.dance/#788d0824269bef539fe31a785b1517882eafed93Patch
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/io_uring?h=linux-5.10.y&id=788d0824269bef539fe31a785b1517882eafed93Mailing List, Patch
- https://kernel.dance/#788d0824269bef539fe31a785b1517882eafed93Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.