CVE-2023-1252: Use After Free
A flaw found in the Linux Kernel. For the Ext4 file system if overlay FS being used, use after free could happen as result of the race condition. The bug actual if patch 9a2544037600 not applied yet. Example for triggering in a overlay on ext4 setup:
aioread ovlreaditer vfsiterread ext4filereaditer ext4dioreaditer iomapdiorw -> -EIOCBQUEUED / Here IO is completed in a separate thread, ovlaiocleanuphandler() frees aioreq which has iocb embedded / fileaccessed(iocb->kifilp); /BOOM/
Reference: https://lore.kernel.org/lkml/20211115165433.449951285@linuxfoundation.org/
Other sources
A use-after-free flaw was found in the Linux kernel’s Ext4 File System in how a user triggers several file operations simultaneously with the overlay FS usage. This flaw allows a local user to crash or potentially escalate their privileges on the system. Only if patch 9a2544037600 ("ovl: fix use after free in struct ovlaioreq") not applied yet, the kernel could be affected.
Linux Kernel could allow a local authenticated attacker to gain elevated privileges on the system, caused by a use-after-free flaw in the Ext4 File System. An attacker could exploit this vulnerability to gain elevated privileges.
— IBM
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2023-1252?
CVE-2023-1252 has a high severity due to the potential for a use-after-free condition leading to system instability.
How do I fix CVE-2023-1252?
To fix CVE-2023-1252, ensure that the patch identified as 9a2544037600 is applied to your kernel.
Which versions of the Linux kernel are affected by CVE-2023-1252?
CVE-2023-1252 affects Linux kernel versions older than 5.16 if patch 9a2544037600 is not applied.
What systems are impacted by CVE-2023-1252?
CVE-2023-1252 impacts systems using the Ext4 file system with overlay filesystem enabled.
Is CVE-2023-1252 specific to any vendor software?
Yes, CVE-2023-1252 affects IBM's Security Verify Governance, Identity Manager software component up to version 10.0.2.