CVE-2026-31699

Technical Description

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

crypto: ccp: Don't attempt to copy CSR to userspace if PSP command failed

When retrieving the PEK CSR, don't attempt to copy the blob to userspace

if the firmware command failed. If the failure was due to an invalid

length, i.e. the userspace buffer+length was too small, copying the number

of bytes _firmware_ requires will overflow the kernel-allocated buffer and

leak data to userspace.

BUG: KASAN: slab-out-of-bounds in instrument_copy_to_user ../include/linux/instrumented.h:129 [inline]

BUG: KASAN: slab-out-of-bounds in _inline_copy_to_user ../include/linux/uaccess.h:205 [inline]

BUG: KASAN: slab-out-of-bounds in _copy_to_user+0x66/0xa0 ../lib/usercopy.c:26

Read of size 2084 at addr ffff898144612e20 by task syz.9.219/21405

CPU: 14 UID: 0 PID: 21405 Comm: syz.9.219 Tainted: G U O 7.0.0-smp-DEV #28 PREEMPTLAZY

Tainted: [U]=USER, [O]=OOT_MODULE

Hardware name: Google, Inc. Arcadia_IT_80/A

Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

Affected Products

References