#VU124523 Out-of-bounds read in Linux kernel - CVE-2026-23327
Published: March 25, 2026
Vulnerability identifier: #VU124523
Vulnerability risk: Low
CVSSv4.0: 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
CVE-ID: CVE-2026-23327
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerable software:
Linux kernel
Linux kernel
Software vendor:
Linux Foundation
Linux Foundation
Description
The vulnerability allows a local user to cause a denial of service, disclose sensitive information, and potentially execute arbitrary code.
The vulnerability exists due to improper input validation in the CXL mailbox command handler when processing user-supplied payloads. A local user can send a specially crafted raw mailbox command with an undersized payload to trigger an out-of-bounds read in the kernel, leading to memory disclosure, system crash, or potential code execution.
The issue specifically occurs in the cxl_payload_from_user_allowed() function, where the payload size is not validated before accessing its contents, resulting in a slab-out-of-bounds read during UUID comparison.
Remediation
Install security update from vendor's repository.