GHSA-F7Q5-FWF8-R5Q4
Vulnerability from github – Published: 2025-02-27 21:32 – Updated: 2025-02-27 21:32In 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.
{
"affected": [],
"aliases": [
"CVE-2025-21818"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-02-27T20:16:04Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/xen: fix xen_hypercall_hvm() to not clobber %rbx\n\nxen_hypercall_hvm(), which is used when running as a Xen PVH guest at\nmost only once during early boot, is clobbering %rbx. Depending on\nwhether the caller relies on %rbx to be preserved across the call or\nnot, this clobbering might result in an early crash of the system.\n\nThis can be avoided by using an already saved register instead of %rbx.",
"id": "GHSA-f7q5-fwf8-r5q4",
"modified": "2025-02-27T21:32:17Z",
"published": "2025-02-27T21:32:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-21818"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/23f6f420cd727d641f95478fcf3bbbee41e4e5d6"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/242f7584da3ad041a9db809d33d27a8be8eccc29"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4890a0858c09d96f3234a8f94663de80a7201bc4"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/522d726824cc570e0b6bf0b3af4d5a826f1b17c5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/98a5cfd2320966f40fe049a9855f8787f0126825"
}
],
"schema_version": "1.4.0",
"severity": []
}
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| Author | Source | Type | Date | Other |
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Nomenclature
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Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
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