cbcvebase.
CVE-2021-20177
published 2021-05-26

CVE-2021-20177: A flaw was found in the Linux kernel's implementation of string matching within a packet. A privileged user (with root or CAP_NET_ADMIN) when inserting…

PriorityP415medium4.4CVSS 3.1
AVLACLPRHUINSUCNINAH
EPSS
0.28%
20.0th percentile
A flaw was found in the Linux kernel's implementation of string matching within a packet. A privileged user (with root or CAP_NET_ADMIN) when inserting iptables rules could insert a rule which can panic the system. Kernel before kernel 5.5-rc1 is affected.

Affected

8 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.5.13-1 (bookworm)linux 5.5.13-1 (bookworm)
linuxlinux_kernel<= 5.4.9
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.5.13-15.5.13-1
linuxlinux_kernel>= 0 < 5.5.13-15.5.13-1
linuxlinux_kernel>= 0 < 5.5.13-15.5.13-1
linuxlinux_kernel>= 0 < 5.5.13-15.5.13-1
linuxlinux_kernel>= 0 < 5.4.0-66.745.4.0-66.74

CVSS provenance

nvdv3.14.4MEDIUMCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
nvdv2.02.1LOWAV:L/AC:L/Au:N/C:N/I:N/A:P
osv7.8HIGH
vendor_ubuntu7.8HIGH
vendor_debian4.4MEDIUM
vendor_redhat4.4MEDIUM
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