logo_clicknbuy.png

CVE-2025-21818 – Xen Linux XenPVH Guest Register Clobber Vulnerability

The following table lists the changes that have been made to the
CVE-2025-21818 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution
of a vulnerability, and for identifying the most recent changes that may
impact the vulnerability’s severity, exploitability, or other characteristics.

  • New CVE Received
    by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Feb. 27, 2025

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved:

    x86/xen: fix xen_hypercall_hvm() to not clobber %rbx

    xen_hypercall_hvm(), which is used when running as a Xen PVH guest at
    most only once during early boot, is clobbering %rbx. Depending on
    whether the caller relies on %rbx to be preserved across the call or
    not, this clobbering might result in an early crash of the system.

    This can be avoided by using an already saved register instead of %rbx.
    Added Reference https://git.kernel.org/stable/c/23f6f420cd727d641f95478fcf3bbbee41e4e5d6
    Added Reference https://git.kernel.org/stable/c/242f7584da3ad041a9db809d33d27a8be8eccc29
    Added Reference https://git.kernel.org/stable/c/4890a0858c09d96f3234a8f94663de80a7201bc4
    Added Reference https://git.kernel.org/stable/c/522d726824cc570e0b6bf0b3af4d5a826f1b17c5
    Added Reference https://git.kernel.org/stable/c/98a5cfd2320966f40fe049a9855f8787f0126825
Share the Post:

Related Posts