CVE-2023-1252 — A use-after-free flaw was found in the Linux kernel’s Ext4 File System in how a

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 9a254403760

01What is this vulnerability?

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 ovl_aio_req") not applied yet, the kernel could be affected.

02Affected products

Vendor	Product	Versions
n	a / Kernel	Linux kernel 5.16-rc1

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2023-03-23T00:00:00.000Z
• Last modified: 2025-04-23T16:23:30.792Z

09References

• lore.kernel.org — https://lore.kernel.org/lkml/20211115165433.449951285%40linuxfoundation.org/
• security.netapp.com — https://security.netapp.com/advisory/ntap-20230505-0005/