Out-of-bounds read in Linux kernel - CVE-2026-31699
Published: May 2, 2026
Vulnerability identifier: #VU129000
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-31699
CWE-ID: CWE-125
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 an out-of-bounds read in the sev_ioctl_do_pek_csr ioctl handler when processing a PEK CSR retrieval request after a failed firmware command. A local user can supply a too-small userspace buffer and length to trigger a copy to userspace that discloses sensitive information.
The issue occurs when the firmware reports an invalid length for the requested blob.
How to mitigate CVE-2026-31699
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/111dcc6d0f016076745824a787d25609d0022f4c
- https://git.kernel.org/stable/c/3b4fd8f15765d9a3105b834dba8a05d025e5e16e
- https://git.kernel.org/stable/c/59e9ae81f8670ccc780bc75f45a355736f640ec9
- https://git.kernel.org/stable/c/607ba280f2adb5092cf5386c3935afac2ca0031a
- https://git.kernel.org/stable/c/abe4a6d6f606113251868c2c4a06ba904bb41eed