CVE-2018-20784

In the Linux kernel before 4.20.2, kernel/sched/fair.c mishandles leaf cfs_rq's, which allows attackers to cause a denial of service (infinite loop in update_blocked_averages) or possibly have unspecified other impact by inducing a high load.

CVSS v3.0 9.8 CRITICAL
CVSS v2.0 7.5 HIGH

9.8^/10

CVSS v3.0 : CRITICAL

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

V2 Legend

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://github.com/torvalds/linux/commit/c40f7d74c741a907cfaeb73a7697081881c497d0	Patch Third Party Advisory
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.20.2	Release Notes Vendor Advisory
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=c40f7d74c741a907cfaeb73a7697081881c497d0	Patch Vendor Advisory
https://access.redhat.com/errata/RHSA-2019:1959	Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:1971	Third Party Advisory
https://usn.ubuntu.com/4115-1/	Third Party Advisory
https://usn.ubuntu.com/4118-1/	Third Party Advisory
https://usn.ubuntu.com/4211-2/	Third Party Advisory
https://usn.ubuntu.com/4211-1/	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:5.0:rc1::::::

Configuration 2 (hide)

OR	cpe:2.3:o:canonical:ubuntu_linux:14.04::::esm:::
	cpe:2.3:o:canonical:ubuntu_linux:16.04::::esm:::
	cpe:2.3:o:canonical:ubuntu_linux:18.04::::lts:::

Configuration 3 (hide)

OR	cpe:2.3:o:redhat:enterprise_linux:8.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux_for_real_time:8:::::::*

Information

Published : 2019-02-22 07:29

Updated : 2021-06-02 08:28

NVD link : CVE-2018-20784

Mitre link : CVE-2018-20784

JSON object : View

CWE

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

Products Affected

redhat

enterprise_linux
enterprise_linux_for_real_time

canonical

ubuntu_linux

linux

linux_kernel

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9.8 /10