CVE-2026-23215

/// Technical description

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

x86/vmware: Fix hypercall clobbers

Fedora QA reported the following panic:

BUG: unable to handle page fault for address: 0000000040003e54

#PF: supervisor write access in kernel mode

#PF: error_code(0x0002) - not-present page

Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20251119-3.fc43 11/19/2025

RIP: 0010:vmware_hypercall4.constprop.0+0x52/0x90

..

Call Trace:

vmmouse_report_events+0x13e/0x1b0

psmouse_handle_byte+0x15/0x60

ps2_interrupt+0x8a/0xd0

...

because the QEMU VMware mouse emulation is buggy, and clears the top 32

bits of %rdi that the kernel kept a pointer in.

The QEMU vmmouse driver saves and restores the register state in a

"uint32_t data[6];" and as a result restores the state with the high

bits all cleared.

RDI originally contained the value of a valid kernel stack address

(0xff5eeb3240003e54). After the vmware hypercall it now contains

0x40003e54, and we get

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. 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.

/// References