Cloudanix VulnDB

CVE-2023-54056

None

CVSS

—

EPSS

0.2%

Published

Dec 24, 2025

CISA due date

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Cloudanix analysis

Schedule a fix SSVC: Track

A coding mistake in the Linux kernel can cause the whole computer to crash when certain internal data files are read.

Exploitation
Local Privilege
Attacker needs
Local User
Complexity
Trivial
Impact
Denial Of Service
Component
OS kernel
Class
Buffer Overflow
Remediation
Upgrade
Effort
Medium
Patch risk
Low

What it actually does

Incorrect declaration of kernel_headers_data as char instead of byte array causes FORTIFY_SOURCE memcpy bounds check to trigger a kernel panic during reads of /sys/kernel/kheaders.tar.xz.

Why it matters to the business

Systems may crash or become unstable when users or monitoring tools access kernel header data, leading to unplanned downtime and requiring reboots.

How an attack unfolds

An attacker or automated process opens the kheaders sysfs file for reading; the kernel module performs a memcpy that FORTIFY_SOURCE detects as an overflow, immediately triggering a BUG and kernel panic.

How to fix it

Update the Linux kernel to commit 719459877d58c8aced5845c1e5b98d8d87d09197 or later; rebuild and deploy any affected packages such as kafka_exporter to versions 1.9.0-r36 or newer.

How to confirm the fix worked

Confirm the updated kernel is running, then verify that reading /sys/kernel/kheaders.tar.xz completes without triggering a fortify_panic or kernel BUG.

Typical attack path

  1. Locate or trigger access to /sys/kernel/kheaders.tar.xz
  2. Initiate a read operation on the file
  3. Kernel executes ikheaders_read which performs unsafe memcpy
  4. FORTIFY_SOURCE check fails and calls fortify_panic

How to detect it

Search kernel logs for fortify_panic, detected buffer overflow in memcpy, and call traces containing ikheaders_read or kernfs_fop_read_iter.

What your security team should do

  • Prioritize kernel updates on all systems exposing the kheaders interface
  • Monitor for kernel panics referencing fortify_panic or ikheaders_read
  • Audit workloads that access /sys/kernel/kheaders.tar.xz and restrict access where possible

The record

In the Linux kernel, the following vulnerability has been resolved: kheaders: Use array declaration instead of char Under CONFIG_FORTIFY_SOURCE, memcpy() will check the size of destination and source buffers. Defining kernel_headers_data as "char" would trip this check. Since these addresses are treated as byte arrays, define them as arrays (as done everywhere else). This was seen with: $ cat /sys/kernel/kheaders.tar.xz >> /dev/null detected buffer overflow in memcpy kernel BUG at lib/string_helpers.c:1027! ... RIP: 0010:fortify_panic+0xf/0x20 [...] Call Trace: <TASK> ikheaders_read+0x45/0x50 [kheaders] kernfs_fop_read_iter+0x1a4/0x2f0 ...

Affected packages

Ecosystem Package Introduced Fixed
Linux Kernel 5.2.0 5.4.243

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