Use After Free Affecting kernel-libbpf package, versions <0:6.1.21-1.45.amzn2023


Severity

Recommended
high

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.03% (6th percentile)

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  • Snyk IDSNYK-AMZN2023-KERNELLIBBPF-11444164
  • published5 Aug 2025
  • disclosed2 May 2025

Introduced: 2 May 2025

CVE-2023-53111  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 kernel-libbpf to version 0:6.1.21-1.45.amzn2023 or higher.
This issue was patched in ALAS2023-2023-148.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-libbpf package and not the kernel-libbpf package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

loop: Fix use-after-free issues

do_req_filebacked() calls blk_mq_complete_request() synchronously or asynchronously when using asynchronous I/O unless memory allocation fails. Hence, modify loop_handle_cmd() such that it does not dereference 'cmd' nor 'rq' after do_req_filebacked() finished unless we are sure that the request has not yet been completed. This patch fixes the following kernel crash:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000054 Call trace: css_put.42938+0x1c/0x1ac loop_process_work+0xc8c/0xfd4 loop_rootcg_workfn+0x24/0x34 process_one_work+0x244/0x558 worker_thread+0x400/0x8fc kthread+0x16c/0x1e0 ret_from_fork+0x10/0x20

CVSS Base Scores

version 3.1