CVE-2023-23586

A use-after-free vulnerability was discovered in the Linux kernel's io_uring subsystem. It was found that it is possible to insert a time namespace's vvar page to process 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. This (read-only) use-after-free vulnerability can lead to kernel memory leak.

Red Hat Enterprise Linux is not affected by this flaw, as the io_uring subsystem (CONFIG_IO_URING) is not supported in any current shipping kernels.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.