CVE-2021-26932

Published Feb 17, 2021

Last updated 8 months ago

Overview

Description
An issue was discovered in the Linux kernel 3.2 through 5.10.16, as used by Xen. Grant mapping operations often occur in batch hypercalls, where a number of operations are done in a single hypercall, the success or failure of each one is reported to the backend driver, and the backend driver then loops over the results, performing follow-up actions based on the success or failure of each operation. Unfortunately, when running in PV mode, the Linux backend drivers mishandle this: Some errors are ignored, effectively implying their success from the success of related batch elements. In other cases, errors resulting from one batch element lead to further batch elements not being inspected, and hence successful ones to not be possible to properly unmap upon error recovery. Only systems with Linux backends running in PV mode are vulnerable. Linux backends run in HVM / PVH modes are not vulnerable. This affects arch/*/xen/p2m.c and drivers/xen/gntdev.c.
Source
cve@mitre.org
NVD status
Modified

Social media

Hype score
Not currently trending

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

CVSS 2.0

Type
Primary
Base score
1.9
Impact score
2.9
Exploitability score
3.4
Vector string
AV:L/AC:M/Au:N/C:N/I:N/A:P

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Configurations