CVE-2021-0293 MEDIUM

CVE-2021-0293: Junos OS: Out-of-memory condition and crashes can occur after executing a certain CLI command repeatedly

Vendor Juniper Networks
Product Junos OS
Weakness CWE-401
Published July 15, 2021
Last update September 16, 2024

CVSS base score

5.5/10
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality None
Integrity None

CVSS vector

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

What the vulnerability does

01Description

A vulnerability in Juniper Networks Junos OS caused by Missing Release of Memory after Effective Lifetime leads to a memory leak each time the CLI command 'show system connections extensive' is executed. The amount of memory leaked on each execution depends on the number of TCP connections from and to the system. Repeated execution will cause more memory to leak and eventually daemons that need to allocate additionally memory and ultimately the kernel to crash, which will result in traffic loss. Continued execution of this command will cause a sustained Denial of Service (DoS) condition. An administrator can use the following CLI command to monitor for increase in memory consumption of the netstat process, if it exists: user@junos> show system processes extensive | match "username|netstat" PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU COMMAND 21181 root 100 0 5458M 4913M CPU3 2 0:59 97.27% netstat The following log message might be observed if this issue happens: kernel: %KERN-3: pid 21181 (netstat), uid 0, was killed: out of swap space This issue affects Juniper Networks Junos OS 18.2 versions prior to 18.2R2-S8, 18.2R3-S7. 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S6, 18.4R3-S7; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R2-S6, 19.3R3-S1; 19.4 versions prior to 19.4R1-S4, 19.4R2-S3, 19.4R3-S1; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S1, 20.3R2; This issue does not affect Juniper Networks Junos OS versions prior to 18.2R1.

Key dates

02Disclosure timeline

July 15, 2021 CVE published
September 16, 2024 Record updated