cbcvebase.
CVE-2020-27777
published 2020-12-15

CVE-2020-27777: A flaw was found in the way RTAS handled memory accesses in userspace to kernel communication. On a locked down (usually due to Secure Boot) guest system…

PriorityP429medium6.7CVSS 3.1
AVLACLPRHUINSUCHIHAH
EPSS
0.50%
39.6th percentile
A flaw was found in the way RTAS handled memory accesses in userspace to kernel communication. On a locked down (usually due to Secure Boot) guest system running on top of PowerVM or KVM hypervisors (pseries platform) a root like local user could use this flaw to further increase their privileges to that of a running kernel.

Affected

21 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.9.6-1 (bookworm)linux 5.9.6-1 (bookworm)
linuxlinux_kernel< 4.14.2044.14.204
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.9.6-15.9.6-1
linuxlinux_kernel>= 0 < 5.9.6-15.9.6-1
linuxlinux_kernel>= 0 < 5.9.6-15.9.6-1
linuxlinux_kernel>= 0 < 5.9.6-15.9.6-1
linuxlinux_kernel>= 0 < 4.4.0-201.2334.4.0-201.233
linuxlinux_kernel>= 0 < 4.15.0-129.1324.15.0-129.132
linuxlinux_kernel>= 0 < 5.4.0-59.655.4.0-59.65
linuxlinux_kernel>= 4.15 < 4.19.1554.19.155
linuxlinux_kernel>= 4.20 < 5.4.755.4.75
linuxlinux_kernel>= 5.5 < 5.9.55.9.5
msrccm1_kernel_5.4.91-1_on_cbl_mariner_1.0
redhatenterprise_linux
redhatenterprise_linux
redhatenterprise_linux
redhatenterprise_linux
redhatopenshift_container_platform
redhatopenshift_container_platform
redhatopenshift_container_platform

CVSS provenance

nvdv3.16.7MEDIUMCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.2HIGHAV:L/AC:L/Au:N/C:C/I:C/A:C
osv8.2HIGH
vendor_ubuntu8.2HIGH
vendor_debian6.7MEDIUM
vendor_msrc6.7MEDIUM
vendor_redhat6.7MEDIUM
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