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High · 7.1 CVE-2021-31360 EUVD-2021-18270GHSA-j6cc-h7v7-4cvc

Junos OS and Junos OS Evolved: Denial of Service vulnerability in local file processing

Published Oct 19, 2021 · Updated Sep 17, 2024 · Assigned by juniper

Description

An improper privilege management vulnerability in the Juniper Networks Junos OS and Junos OS Evolved command-line interpreter (CLI) allows a low-privileged user to overwrite local files as root, possibly leading to a system integrity issue or Denial of Service (DoS). Depending on the files overwritten, exploitation of this vulnerability could lead to a sustained Denial of Service (DoS) condition, requiring manual user intervention to recover. Systems are only vulnerable if jdhcpd is running, which can be confirmed via the 'show system processes' command. For example: root@host# run show system processes extensive | match dhcp 26537 root -16 0 97568K 13692K RUN 0 0:01 3.71% jdhcpd This issue affects: Juniper Networks Junos OS: All versions, including the following supported releases: 15.1 versions prior to 15.1R7-S10; 17.4 versions prior to 17.4R3-S5; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R3-S9; 19.1 versions prior to 19.1R3-S6; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R3-S6; 20.1 versions prior to 20.1R2-S2, 20.1R3-S1; 20.2 versions prior to 20.2R3-S2; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2-S1, 20.4R3; 21.1 versions prior to 21.1R1-S1, 21.1R2. Juniper Networks Junos OS Evolved: All versions prior to 20.4R2-S3-EVO; All versions of 21.1-EVO.

Affected products

VendorProductAffectedFixed
Juniper Networks Junos OS 15.1 – < 15.1R7-S10, 17.4 – < 17.4R3-S5, 18.3 – < 18.3R3-S5, 18.4 – < 18.4R3-S9, 19.1 – < 19.1R3-S6, 19.2 – < 19.2R1-S7, 19.2R3-S3, 19.3 – < 19.3R2-S6, 19.3R3-S3, 19.4 – < 19.4R3-S6, 20.1 – < 20.1R2-S2, 20.1R3-S1, 20.2 – < 20.2R3-S2, 20.3 – < 20.3R3, 20.4 – < 20.4R2-S1, 20.4R3, 21.1 – < 21.1R1-S1, … 15.1R7-S10
Juniper Networks Junos OS Evolved unspecified – < 20.4R2-S3-EVO, 21.1R1-EVO – < 21.1* 20.4R2-S3-EVO

References