SB20250619171 - Use-after-free in Linux kernel fs

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2022-49995)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error within the wb_inode_writeback_start() and wb_inode_writeback_end() functions in mm/page-writeback.c, within the wb_wakeup_delayed() and cgwb_remove_from_bdi_list() functions in mm/backing-dev.c, within the inode_io_list_move_locked(), wb_queue_work() and get_next_work_item() functions in fs/fs-writeback.c. A local user can escalate privileges on the system.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/9a6c710f3bc10bc9cc23e1c080b53245b7f9d5b7
• https://git.kernel.org/stable/c/f87904c075515f3e1d8f4a7115869d3b914674fd
• https://git.kernel.org/stable/c/f96b9f7c1676923bce871e728bb49c0dfa5013cc
• https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.64