CVE-2019-20794

An issue was discovered in the Linux kernel 4.18 through 5.6.11 when unprivileged user namespaces are allowed. A user can create their own PID namespace, and mount a FUSE filesystem. Upon interaction with this FUSE filesystem, if the userspace component is terminated via a kill of the PID namespace's pid 1, it will result in a hung task, and resources being permanently locked up until system reboot. This can result in resource exhaustion.

CVSS v3.0 4.7 MEDIUM
CVSS v2.0 4.7 MEDIUM

4.7^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

4.7^/10

CVSS v2.0 : MEDIUM

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

Exploitability : 3.4 / Impact : 6.9

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact COMPLETE

References

Link	Resource
https://github.com/sargun/fuse-example	Exploit Third Party Advisory
https://sourceforge.net/p/fuse/mailman/message/36598753/	Exploit Third Party Advisory
https://security.netapp.com/advisory/ntap-20200608-0001/	Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/08/24/1	Mailing List Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

Information

Published : 2020-05-09 11:15

Updated : 2021-07-21 04:39

NVD link : CVE-2019-20794

Mitre link : CVE-2019-20794

JSON object : View

CWE

CWE-772

Missing Release of Resource after Effective Lifetime

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Products Affected

linux

linux_kernel

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