CVE-2021-46910

2024-02-2720:42:30

redhat.com

access.redhat.com

linux kernel

kmap_local

fixmap region

virtual dt mapping

5.5 Medium

CVSS3

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

6.4 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

9.1%

JSON

A flaw was found in kmap_local() in the Linux Kernel that doubles the number of per-CPU fixmap slots allocated for kmap_local(). This causes the fixmap region to grow downwards beyond the start of its reserved window if the supported number of CPUs is large, eventually colliding with the newly added virtual DT mapping below it.