medium
5.3
CWE
770
Advisory Published
Updated

CVE-2021-31369: Junos OS: MX Series: Traffic drops will be observed if MS-MPC/MS-PIC resources are consumed by certain traffic causing a partial DoS

First published: Wed Oct 13 2021(Updated: )

On MX Series platforms with MS-MPC/MS-MIC, an Allocation of Resources Without Limits or Throttling vulnerability in Juniper Networks Junos OS allows an unauthenticated network attacker to cause a partial Denial of Service (DoS) with a high rate of specific traffic. If a Class of Service (CoS) rule is attached to the service-set and a high rate of specific traffic is processed by this service-set, for some of the other traffic which has services applied and is being processed by this MS-MPC/MS-MIC drops will be observed. Continued receipted of this high rate of specific traffic will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS on MX Series with MS-MPC/MS-MIC: All 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-S7, 19.3R3-S3; 19.4 versions prior to 19.4R3-S5; 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.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Junos OS Evolved<17.4
Junos OS Evolved=17.4
Junos OS Evolved=17.4-r1
Junos OS Evolved=17.4-r1-s1
Junos OS Evolved=17.4-r1-s2
Junos OS Evolved=17.4-r1-s3
Junos OS Evolved=17.4-r1-s4
Junos OS Evolved=17.4-r1-s5
Junos OS Evolved=17.4-r1-s6
Junos OS Evolved=17.4-r1-s7
Junos OS Evolved=17.4-r2
Junos OS Evolved=17.4-r2-s1
Junos OS Evolved=17.4-r2-s10
Junos OS Evolved=17.4-r2-s11
Junos OS Evolved=17.4-r2-s12
Junos OS Evolved=17.4-r2-s13
Junos OS Evolved=17.4-r2-s2
Junos OS Evolved=17.4-r2-s3
Junos OS Evolved=17.4-r2-s4
Junos OS Evolved=17.4-r2-s5
Junos OS Evolved=17.4-r2-s6
Junos OS Evolved=17.4-r2-s7
Junos OS Evolved=17.4-r2-s8
Junos OS Evolved=17.4-r2-s9
Junos OS Evolved=17.4-r3
Junos OS Evolved=17.4-r3-s1
Junos OS Evolved=17.4-r3-s2
Junos OS Evolved=17.4-r3-s3
Junos OS Evolved=17.4-r3-s4
Junos OS Evolved=18.3
Junos OS Evolved=18.3-r
Junos OS Evolved=18.3-r1
Junos OS Evolved=18.3-r1-s1
Junos OS Evolved=18.3-r1-s2
Junos OS Evolved=18.3-r1-s3
Junos OS Evolved=18.3-r1-s4
Junos OS Evolved=18.3-r1-s5
Junos OS Evolved=18.3-r1-s6
Junos OS Evolved=18.3-r2
Junos OS Evolved=18.3-r2-s1
Junos OS Evolved=18.3-r2-s2
Junos OS Evolved=18.3-r2-s3
Junos OS Evolved=18.3-r2-s4
Junos OS Evolved=18.3-r3
Junos OS Evolved=18.3-r3-s1
Junos OS Evolved=18.3-r3-s2
Junos OS Evolved=18.3-r3-s3
Junos OS Evolved=18.3-r3-s4
Junos OS Evolved=18.4
Junos OS Evolved=18.4-r1
Junos OS Evolved=18.4-r1-s1
Junos OS Evolved=18.4-r1-s2
Junos OS Evolved=18.4-r1-s3
Junos OS Evolved=18.4-r1-s4
Junos OS Evolved=18.4-r1-s5
Junos OS Evolved=18.4-r1-s6
Junos OS Evolved=18.4-r1-s7
Junos OS Evolved=18.4-r2
Junos OS Evolved=18.4-r2-s1
Junos OS Evolved=18.4-r2-s2
Junos OS Evolved=18.4-r2-s3
Junos OS Evolved=18.4-r2-s4
Junos OS Evolved=18.4-r2-s5
Junos OS Evolved=18.4-r2-s6
Junos OS Evolved=18.4-r2-s7
Junos OS Evolved=18.4-r2-s8
Junos OS Evolved=18.4-r3
Junos OS Evolved=18.4-r3-s1
Junos OS Evolved=18.4-r3-s2
Junos OS Evolved=18.4-r3-s3
Junos OS Evolved=18.4-r3-s4
Junos OS Evolved=18.4-r3-s5
Junos OS Evolved=18.4-r3-s6
Junos OS Evolved=18.4-r3-s7
Junos OS Evolved=18.4-r3-s8
Junos OS Evolved=19.1
Junos OS Evolved=19.1-r1
Junos OS Evolved=19.1-r1-s1
Junos OS Evolved=19.1-r1-s2
Junos OS Evolved=19.1-r1-s3
Junos OS Evolved=19.1-r1-s4
Junos OS Evolved=19.1-r1-s5
Junos OS Evolved=19.1-r1-s6
Junos OS Evolved=19.1-r2
Junos OS Evolved=19.1-r2-s1
Junos OS Evolved=19.1-r2-s2
Junos OS Evolved=19.1-r2-s3
Junos OS Evolved=19.1-r3
Junos OS Evolved=19.1-r3-s1
Junos OS Evolved=19.1-r3-s2
Junos OS Evolved=19.1-r3-s3
Junos OS Evolved=19.1-r3-s4
Junos OS Evolved=19.1-r3-s5
Junos OS Evolved=19.2
Junos OS Evolved=19.2-r1
Junos OS Evolved=19.2-r1-s1
Junos OS Evolved=19.2-r1-s2
Junos OS Evolved=19.2-r1-s3
Junos OS Evolved=19.2-r1-s4
Junos OS Evolved=19.2-r1-s5
Junos OS Evolved=19.2-r1-s6
Junos OS Evolved=19.2-r3
Junos OS Evolved=19.2-r3-s1
Junos OS Evolved=19.2-r3-s2
Junos OS Evolved=19.3
Junos OS Evolved=19.3-r1
Junos OS Evolved=19.3-r1-s1
Junos OS Evolved=19.3-r2
Junos OS Evolved=19.3-r2-s1
Junos OS Evolved=19.3-r2-s2
Junos OS Evolved=19.3-r2-s3
Junos OS Evolved=19.3-r2-s4
Junos OS Evolved=19.3-r2-s5
Junos OS Evolved=19.3-r2-s6
Junos OS Evolved=19.3-r3
Junos OS Evolved=19.3-r3-s1
Junos OS Evolved=19.3-r3-s2
Junos OS Evolved=19.4-r1
Junos OS Evolved=19.4-r1-s1
Junos OS Evolved=19.4-r1-s2
Junos OS Evolved=19.4-r1-s3
Junos OS Evolved=19.4-r1-s4
Junos OS Evolved=19.4-r2
Junos OS Evolved=19.4-r2-s1
Junos OS Evolved=19.4-r2-s2
Junos OS Evolved=19.4-r2-s3
Junos OS Evolved=19.4-r2-s4
Junos OS Evolved=19.4-r2-s5
Junos OS Evolved=19.4-r3
Junos OS Evolved=19.4-r3-s1
Junos OS Evolved=19.4-r3-s2
Junos OS Evolved=19.4-r3-s3
Junos OS Evolved=19.4-r3-s4
Junos OS Evolved=20.1-r1
Junos OS Evolved=20.1-r1-s1
Junos OS Evolved=20.1-r1-s2
Junos OS Evolved=20.1-r1-s3
Junos OS Evolved=20.1-r1-s4
Junos OS Evolved=20.1-r2
Junos OS Evolved=20.1-r2-s1
Junos OS Evolved=20.1-r3
Junos OS Evolved=20.2-r1
Junos OS Evolved=20.2-r1-s1
Junos OS Evolved=20.2-r1-s2
Junos OS Evolved=20.2-r1-s3
Junos OS Evolved=20.2-r2
Junos OS Evolved=20.2-r2-s1
Junos OS Evolved=20.2-r2-s2
Junos OS Evolved=20.2-r2-s3
Junos OS Evolved=20.2-r3
Junos OS Evolved=20.2-r3-s1
Junos OS Evolved=20.3-r1
Junos OS Evolved=20.3-r1-s1
Junos OS Evolved=20.3-r2
Junos OS Evolved=20.3-r2-s1
Junos OS Evolved=20.4-r1
Junos OS Evolved=20.4-r1-s1
Junos OS Evolved=20.4-r2
Junos OS Evolved=21.1-r1
Juniper MX10
Juniper MX10000
Juniper MX10003
Juniper MX10008
Juniper MX10016
Juniper MX104
Juniper MX150
Juniper MX2008
Juniper MX2010
Juniper MX2020
Juniper MX204
Juniper MX240
Juniper MX40
Juniper MX480
Juniper MX5
Juniper MX80
Juniper MX960

Remedy

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

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-31369?

    CVE-2021-31369 is classified as a high severity vulnerability due to its potential to cause a partial Denial of Service (DoS).

  • How do I fix CVE-2021-31369?

    To mitigate CVE-2021-31369, users should upgrade to the fixed versions of Junos OS that address this vulnerability.

  • What products are affected by CVE-2021-31369?

    CVE-2021-31369 affects Juniper Networks Junos OS on MX Series platforms with specific MS-MPC or MS-MIC.

  • Can CVE-2021-31369 be exploited remotely?

    Yes, CVE-2021-31369 can be exploited by unauthenticated network attackers remotely.

  • What are the potential impacts of CVE-2021-31369?

    The primary impact of CVE-2021-31369 is a partial Denial of Service (DoS), which can disrupt network operations.

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