CVE-2020-15852
xen: Linux ioperm bitmap context switching issues
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · July 16, 2020
Updated · June 28, 2026
Description
A flaw was found in the Linux kernel, in the way IOPL and IOPERM system calls were handled during context switches in x86 PV guests. This flaw allows a local guest user to escalate their privileges to the guest. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Statement
The vulnerability can only be exploited in domains which have been granted access to IO ports by Xen. This is typically only the hardware domain, and PV guests configured with PCI passthrough. x86 HVM/PVH guests are not affected by this flaw.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 7CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-270 · Privilege Context Switching Error