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

Summary

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.

Timeline

1. Oct 19, 2021, 6:16 PM UTCCVE published
2. Sep 17, 2024, 1:31 AM UTCRecord last updated

Affected versions

• Juniper Networks Junos OS

  From 15.1 · fixed in 15.1R7-S10; From 17.4 · fixed in 17.4R3-S5; From 18.3 · fixed in 18.3R3-S5; From 18.4 · fixed in 18.4R3-S9; From 19.1 · fixed in 19.1R3-S6; From 19.4 · fixed in 19.4R3-S6; From 20.2 · fixed in 20.2R3-S2; From 20.3 · fixed in 20.3R3

• Juniper Networks Junos OS Evolved

  fixed in 20.4R2-S3-EVO; From 21.1R1-EVO

References 1