Improper Initialization in Linux kernel - CVE-2026-43089
Published: May 7, 2026
Vulnerability identifier: #VU130666
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-43089
CWE-ID: CWE-665
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to disclose sensitive information.
The vulnerability exists due to improper initialization in build_mapping() when copying xfrm_usersa_id structures to userspace. A local user can trigger the affected code path to disclose sensitive information.
The issue is caused by a one-byte padding hole after the proto field that is not cleared before the structure is copied out.
How to mitigate CVE-2026-43089
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/1beb76b2053b68c491b78370794b8ff63c8f8c02
- https://git.kernel.org/stable/c/5a1a4b049ddde41466ccac0daeec326254b133f2
- https://git.kernel.org/stable/c/700c9622b23c33b5933e6dcea816492c064e4e10
- https://git.kernel.org/stable/c/d3125c541a96fb3c0fc7210112684baf22b6c24d
- https://git.kernel.org/stable/c/f779a6b6cdb6e12baa0663063ac59ab2a8f20c0c