high
7.1
CWE
20 269
Advisory Published
Updated

CVE-2021-31360: Junos OS and Junos OS Evolved: Denial of Service vulnerability in local file processing

First published: Tue Oct 19 2021(Updated: )

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.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper Junos=15.1
Juniper Junos=15.1-a1
Juniper Junos=15.1-f
Juniper Junos=15.1-f1
Juniper Junos=15.1-f2
Juniper Junos=15.1-f2-s1
Juniper Junos=15.1-f2-s2
Juniper Junos=15.1-f2-s3
Juniper Junos=15.1-f2-s4
Juniper Junos=15.1-f3
Juniper Junos=15.1-f4
Juniper Junos=15.1-f5
Juniper Junos=15.1-f5-s7
Juniper Junos=15.1-f6
Juniper Junos=15.1-f6-s1
Juniper Junos=15.1-f6-s10
Juniper Junos=15.1-f6-s12
Juniper Junos=15.1-f6-s2
Juniper Junos=15.1-f6-s3
Juniper Junos=15.1-f6-s4
Juniper Junos=15.1-f6-s5
Juniper Junos=15.1-f6-s6
Juniper Junos=15.1-f6-s7
Juniper Junos=15.1-f6-s8
Juniper Junos=15.1-f6-s9
Juniper Junos=15.1-f7
Juniper Junos=15.1-r
Juniper Junos=15.1-r1
Juniper Junos=15.1-r2
Juniper Junos=15.1-r3
Juniper Junos=15.1-r4
Juniper Junos=15.1-r4-s7
Juniper Junos=15.1-r4-s8
Juniper Junos=15.1-r4-s9
Juniper Junos=15.1-r5
Juniper Junos=15.1-r5-s1
Juniper Junos=15.1-r5-s3
Juniper Junos=15.1-r5-s5
Juniper Junos=15.1-r5-s6
Juniper Junos=15.1-r6
Juniper Junos=15.1-r6-s1
Juniper Junos=15.1-r6-s2
Juniper Junos=15.1-r6-s3
Juniper Junos=15.1-r6-s4
Juniper Junos=15.1-r6-s6
Juniper Junos=15.1-r7
Juniper Junos=15.1-r7-s1
Juniper Junos=15.1-r7-s2
Juniper Junos=15.1-r7-s3
Juniper Junos=15.1-r7-s4
Juniper Junos=15.1-r7-s5
Juniper Junos=15.1-r7-s6
Juniper Junos=15.1-r7-s7
Juniper Junos=15.1-r7-s8
Juniper Junos=15.1-r7-s9
Juniper Junos=17.4
Juniper Junos=17.4-r1
Juniper Junos=17.4-r1-s1
Juniper Junos=17.4-r1-s2
Juniper Junos=17.4-r1-s3
Juniper Junos=17.4-r1-s4
Juniper Junos=17.4-r1-s5
Juniper Junos=17.4-r1-s6
Juniper Junos=17.4-r1-s7
Juniper Junos=17.4-r2
Juniper Junos=17.4-r2-s1
Juniper Junos=17.4-r2-s10
Juniper Junos=17.4-r2-s11
Juniper Junos=17.4-r2-s12
Juniper Junos=17.4-r2-s2
Juniper Junos=17.4-r2-s3
Juniper Junos=17.4-r2-s4
Juniper Junos=17.4-r2-s5
Juniper Junos=17.4-r2-s6
Juniper Junos=17.4-r2-s7
Juniper Junos=17.4-r2-s8
Juniper Junos=17.4-r2-s9
Juniper Junos=17.4-r3
Juniper Junos=17.4-r3-s1
Juniper Junos=17.4-r3-s2
Juniper Junos=17.4-r3-s3
Juniper Junos=17.4-r3-s4
Juniper Junos=18.3
Juniper Junos=18.3-r1
Juniper Junos=18.3-r1-s1
Juniper Junos=18.3-r1-s2
Juniper Junos=18.3-r1-s3
Juniper Junos=18.3-r1-s4
Juniper Junos=18.3-r1-s5
Juniper Junos=18.3-r1-s6
Juniper Junos=18.3-r2
Juniper Junos=18.3-r2-s1
Juniper Junos=18.3-r2-s2
Juniper Junos=18.3-r2-s3
Juniper Junos=18.3-r2-s4
Juniper Junos=18.3-r3
Juniper Junos=18.3-r3-s1
Juniper Junos=18.3-r3-s2
Juniper Junos=18.3-r3-s3
Juniper Junos=18.3-r3-s4
Juniper Junos=18.4
Juniper Junos=18.4-r1
Juniper Junos=18.4-r1-s1
Juniper Junos=18.4-r1-s2
Juniper Junos=18.4-r1-s3
Juniper Junos=18.4-r1-s4
Juniper Junos=18.4-r1-s5
Juniper Junos=18.4-r1-s6
Juniper Junos=18.4-r1-s7
Juniper Junos=18.4-r2
Juniper Junos=18.4-r2-s1
Juniper Junos=18.4-r2-s2
Juniper Junos=18.4-r2-s3
Juniper Junos=18.4-r2-s4
Juniper Junos=18.4-r2-s5
Juniper Junos=18.4-r2-s6
Juniper Junos=18.4-r2-s7
Juniper Junos=18.4-r2-s8
Juniper Junos=18.4-r3
Juniper Junos=18.4-r3-s1
Juniper Junos=18.4-r3-s2
Juniper Junos=18.4-r3-s3
Juniper Junos=18.4-r3-s4
Juniper Junos=18.4-r3-s5
Juniper Junos=18.4-r3-s6
Juniper Junos=18.4-r3-s7
Juniper Junos=18.4-r3-s8
Juniper Junos=19.1
Juniper Junos=19.1-r1
Juniper Junos=19.1-r1-s1
Juniper Junos=19.1-r1-s2
Juniper Junos=19.1-r1-s3
Juniper Junos=19.1-r1-s4
Juniper Junos=19.1-r1-s5
Juniper Junos=19.1-r1-s6
Juniper Junos=19.1-r2
Juniper Junos=19.1-r2-s1
Juniper Junos=19.1-r2-s2
Juniper Junos=19.1-r3
Juniper Junos=19.1-r3-s1
Juniper Junos=19.1-r3-s2
Juniper Junos=19.1-r3-s3
Juniper Junos=19.1-r3-s4
Juniper Junos=19.1-r3-s5
Juniper Junos=19.2
Juniper Junos=19.2-r1
Juniper Junos=19.2-r1-s1
Juniper Junos=19.2-r1-s2
Juniper Junos=19.2-r1-s3
Juniper Junos=19.2-r1-s4
Juniper Junos=19.2-r1-s5
Juniper Junos=19.2-r1-s6
Juniper Junos=19.2-r2
Juniper Junos=19.2-r2-s1
Juniper Junos=19.2-r3
Juniper Junos=19.2-r3-s1
Juniper Junos=19.2-r3-s2
Juniper Junos=19.3
Juniper Junos=19.3-r1
Juniper Junos=19.3-r1-s1
Juniper Junos=19.3-r2
Juniper Junos=19.3-r2-s1
Juniper Junos=19.3-r2-s2
Juniper Junos=19.3-r2-s3
Juniper Junos=19.3-r2-s4
Juniper Junos=19.3-r2-s5
Juniper Junos=19.3-r3
Juniper Junos=19.3-r3-s1
Juniper Junos=19.3-r3-s2
Juniper Junos=19.4-r1
Juniper Junos=19.4-r1-s1
Juniper Junos=19.4-r1-s2
Juniper Junos=19.4-r1-s3
Juniper Junos=19.4-r2
Juniper Junos=19.4-r2-s1
Juniper Junos=19.4-r2-s2
Juniper Junos=19.4-r2-s3
Juniper Junos=19.4-r2-s4
Juniper Junos=19.4-r3
Juniper Junos=19.4-r3-s1
Juniper Junos=19.4-r3-s2
Juniper Junos=19.4-r3-s3
Juniper Junos=19.4-r3-s4
Juniper Junos=19.4-r3-s5
Juniper Junos=20.1-r1
Juniper Junos=20.1-r1-s1
Juniper Junos=20.1-r1-s2
Juniper Junos=20.1-r1-s3
Juniper Junos=20.1-r1-s4
Juniper Junos=20.1-r2
Juniper Junos=20.1-r2-s1
Juniper Junos=20.1-r3
Juniper Junos=20.2-r1
Juniper Junos=20.2-r1-s1
Juniper Junos=20.2-r1-s2
Juniper Junos=20.2-r1-s3
Juniper Junos=20.2-r2
Juniper Junos=20.2-r2-s1
Juniper Junos=20.2-r2-s2
Juniper Junos=20.2-r2-s3
Juniper Junos=20.2-r3
Juniper Junos=20.2-r3-s1
Juniper Junos=20.3-r1
Juniper Junos=20.3-r1-s1
Juniper Junos=20.3-r2
Juniper Junos=20.3-r2-s1
Juniper Junos=20.4-r1
Juniper Junos=20.4-r1-s1
Juniper Junos=20.4-r2
Juniper Junos=21.1-r1
Junos OS Evolved<=20.3
Junos OS Evolved=20.4-r1
Junos OS Evolved=20.4-r1-s1
Junos OS Evolved=20.4-r1-s2
Junos OS Evolved=20.4-r2
Junos OS Evolved=20.4-r2-s1
Junos OS Evolved=20.4-r2-s2
Junos OS Evolved=21.1
Junos OS Evolved=21.1-r1
Junos OS Evolved=21.1-r1-s1
Junos OS Evolved=21.1-r2

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS 15.1R7-S10, 17.4R3-S5, 18.3R3-S5, 18.4R3-S9, 19.1R3-S6, 19.2R1-S7, 19.2R3-S3, 19.3R2-S6, 19.3R3-S3, 19.4R3-S6, 20.1R2-S2, 20.1R3-S1, 20.2R3-S2, 20.3R3, 20.4R2-S1, 20.4R3, 21.1R1-S1, 21.1R2, 21.1R3, 21.2R1, and all subsequent releases. Junos OS Evolved 20.4R2-S3-EVO, 21.2R1-EVO, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-31360?

    CVE-2021-31360 is classified as a high-severity vulnerability that can lead to system integrity issues or Denial of Service.

  • How do I fix CVE-2021-31360?

    To fix CVE-2021-31360, you should update to the patched version of Junos OS provided by Juniper Networks.

  • Who is affected by CVE-2021-31360?

    CVE-2021-31360 affects multiple versions of Junos OS, including 15.1 and 17.4 to 21.1 releases.

  • What is the impact of CVE-2021-31360 on systems?

    The impact of CVE-2021-31360 can allow low-privileged users to overwrite local files as root, which may compromise system integrity.

  • Is CVE-2021-31360 being actively exploited?

    There is no specific information indicating that CVE-2021-31360 is actively being exploited in the wild as of the latest updates.

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