Privilege escalation in Juniper Junos
CVE-2021-31360
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.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
EPSS: 0.002 (10.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.
Affected products
- Juniper Junos — versions 15.1, 17.4, 18.3
- Juniper Junos_os_evolved — versions 20.4, 21.1
- Juniper Networks Junos Os — versions 15.1, 17.4, 18.3
- Juniper Networks Junos Os Evolved — versions unspecified, 21.1R1-EVO
Weakness classification (CWE)
References
- sirt@juniper.net (x_refsource_CONFIRM, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-31360?
- CVE-2021-31360 is a high-severity vulnerability in Juniper Junos, classified under Improper Input Validation. CVSS score: 7.1/10. Published 2021-10-19.
- How severe is CVE-2021-31360?
- High severity. CVSS v3 base score is 7.1 out of 10.