# CVE-2023-23586: linux: Due to a vulnerability in the io_uring subsystem, it is possible to leak kernel memory information to the user proces...

CVE-2023-23586 is fixed in linux on 1 platform, first by DEBIAN-CVE-2023-23586, released February 17, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2023-23586
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0027
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 17, 2023

## 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

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.14.6-1 | [DEBIAN-CVE-2023-23586](https://patchblox.com/security/data/fix/linux/debian-cve-2023-23586.md) | Feb 17, 2023 |
| Linux | linux Debian 13.5 (trixie) | 5.14.6-1 | [DEBIAN-CVE-2023-23586](https://patchblox.com/security/data/fix/linux/debian-cve-2023-23586.md) | Feb 17, 2023 |
| Linux | linux Debian 14 | 5.14.6-1 | [DEBIAN-CVE-2023-23586](https://patchblox.com/security/data/fix/linux/debian-cve-2023-23586.md) | Feb 17, 2023 |

---

Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.