medium
5.3
CWE
754 755
Advisory Published
Updated

CVE-2021-31361: Junos OS: QFX Series and PTX Series: FPC resource usage increases when certain packets are processed which are being VXLAN encapsulated

First published: Tue Oct 19 2021(Updated: )

An Improper Check for Unusual or Exceptional Conditions vulnerability combined with Improper Handling of Exceptional Conditions in Juniper Networks Junos OS on QFX Series and PTX Series allows an unauthenticated network based attacker to cause increased FPC CPU utilization by sending specific IP packets which are being VXLAN encapsulated leading to a partial Denial of Service (DoS). Continued receipted of these specific traffic will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS on QFX Series: All versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R2-S8, 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S7, 18.4R3-S7; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R2-S3, 19.4R3-S1; 20.1 versions prior to 20.1R2, 20.1R3; 20.2 versions prior to 20.2R2, 20.2R3; 20.3 versions prior to 20.3R1-S1, 20.3R2. Juniper Networks Junos OS on PTX Series: All 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 19.4R1-S4, 19.4R3-S5; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R3-S1; 20.3 versions prior to 20.3R2-S1, 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
Juniper Junos=17.3
Juniper Junos=17.3-r1
Juniper Junos=17.3-r1-s1
Juniper Junos=17.3-r1-s4
Juniper Junos=17.3-r2
Juniper Junos=17.3-r2-s1
Juniper Junos=17.3-r2-s2
Juniper Junos=17.3-r2-s3
Juniper Junos=17.3-r2-s4
Juniper Junos=17.3-r2-s5
Juniper Junos=17.3-r3
Juniper Junos=17.3-r3
Juniper Junos=17.3-r3-s1
Juniper Junos=17.3-r3-s10
Juniper Junos=17.3-r3-s2
Juniper Junos=17.3-r3-s3
Juniper Junos=17.3-r3-s4
Juniper Junos=17.3-r3-s5
Juniper Junos=17.3-r3-s6
Juniper Junos=17.3-r3-s7
Juniper Junos=17.3-r3-s8
Juniper Junos=17.3-r3-s9
Juniper Junos=17.3r3
Juniper Junos=17.3r3-s2
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=18.1
Juniper Junos=18.1-r1
Juniper Junos=18.1-r2
Juniper Junos=18.1-r2-s1
Juniper Junos=18.1-r2-s2
Juniper Junos=18.1-r2-s4
Juniper Junos=18.1-r3
Juniper Junos=18.1-r3-s1
Juniper Junos=18.1-r3-s10
Juniper Junos=18.1-r3-s11
Juniper Junos=18.1-r3-s2
Juniper Junos=18.1-r3-s3
Juniper Junos=18.1-r3-s4
Juniper Junos=18.1-r3-s5
Juniper Junos=18.1-r3-s6
Juniper Junos=18.1-r3-s7
Juniper Junos=18.1-r3-s8
Juniper Junos=18.1-r3-s9
Juniper Junos=18.2
Juniper Junos=18.2-r1
Juniper Junos=18.2-r1
Juniper Junos=18.2-r1-s2
Juniper Junos=18.2-r1-s3
Juniper Junos=18.2-r1-s4
Juniper Junos=18.2-r1-s5
Juniper Junos=18.2-r2
Juniper Junos=18.2-r2-s1
Juniper Junos=18.2-r2-s2
Juniper Junos=18.2-r2-s3
Juniper Junos=18.2-r2-s4
Juniper Junos=18.2-r2-s5
Juniper Junos=18.2-r2-s6
Juniper Junos=18.2-r2-s7
Juniper Junos=18.2-r3
Juniper Junos=18.2-r3-s1
Juniper Junos=18.2-r3-s2
Juniper Junos=18.2-r3-s3
Juniper Junos=18.2-r3-s4
Juniper Junos=18.2-r3-s5
Juniper Junos=18.2-r3-s6
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=18.4
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-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=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-r2
Juniper Junos=19.1-r2-s1
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=19.2
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-r3
Juniper Junos=19.2-r3-s1
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-r2-s6
Juniper Junos=19.3-r3
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-r1-s4
Juniper Junos=19.4-r2
Juniper Junos=19.4-r2-s1
Juniper Junos=19.4-r2-s2
Juniper Junos=19.4-r3
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=20.2-r1
Juniper Junos=20.2-r1-s1
Juniper Junos=20.2-r1-s2
Juniper Junos=20.2-r1-s3
Juniper Junos=20.3-r1
Juniper QFX10000
Juniper QFX10002-60C
Juniper QFX10002-32Q
Juniper QFX10002-60C
Juniper QFX10002-72Q
Juniper QFX10008
Juniper QFX10016
Juniper QFX10000
Juniper QFX3000-G
Juniper QFX3000-M
Juniper QFX3008-I
Juniper QFX3100
Juniper QFX3500
Juniper QFX3600-I
Juniper QFX3600
Juniper QFX5100
Juniper QFX5100
Juniper QFX5110
Juniper QFX5120
Juniper QFX5130
Juniper QFX5200-48Y
Juniper QFX5200-32C
Juniper QFX5200-48Y
Juniper QFX5210-64C
Juniper QFX5210-64C
Juniper QFX5220
Juniper Junos=18.4-r2-s7
Juniper Junos=18.4-r2-s8
Juniper Junos=18.4-r3-s10
Juniper Junos=18.4-r3-s7
Juniper Junos=18.4-r3-s8
Juniper Junos=19.1-r1-s6
Juniper Junos=19.1-r2-s2
Juniper Junos=19.1-r2-s3
Juniper Junos=19.1-r3-s4
Juniper Junos=19.1-r3-s5
Juniper Junos=19.2-r1-s6
Juniper Junos=19.2-r3-s2
Juniper Junos=19.3-r3-s1
Juniper Junos=19.3-r3-s2
Juniper Junos=19.4-r2-s3
Juniper Junos=19.4-r2-s4
Juniper Junos=19.4-r2-s5
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=20.1-r2
Juniper Junos=20.1-r2-s1
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=20.3-r1-s1
Juniper Junos=20.3-r2
Juniper Junos=20.4-r1
Juniper Junos=20.4-r1-s1
Juniper Junos=20.4-r2
Juniper Junos=21.1-r1
Juniper PTX1000
juniper ptx1000-72q
juniper ptx10000
juniper ptx10001
juniper ptx10001-36mr
juniper ptx100016
juniper ptx10002
juniper ptx10002-60c
juniper ptx10003
juniper ptx10003 160c
juniper ptx10003 80c
juniper ptx10003 81cd
juniper ptx10004
juniper ptx10008
juniper ptx10016
juniper ptx3000
juniper ptx5000

Remedy

https://kb.juniper.net/JSA11223

Remedy

The following software releases have been updated to resolve this specific issue for QFX Series: 17.3R3-S11, 17.4R2-S13, 17.4R3-S4, 18.1R3-S12, 18.2R2-S8, 18.2R3-S7, 18.3R3-S4, 18.4R1-S8, 18.4R2-S7, 18.4R3-S7, 19.1R1-S6, 19.1R2-S2, 19.1R3-S4, 19.2R1-S6, 19.2R3-S2, 19.3R3-S1, 19.4R2-S3, 19.4R3-S1, 20.1R2, 20.1R3, 20.2R2, 20.2R3, 20.3R1-S1, 20.3R2, 20.4R1, and all subsequent releases. The following software releases have been updated to resolve this specific issue for PTX Series: 18.4R3-S9, 19.1R3-S6, 19.2R1-S7, 19.2R3-S3, 19.3R2-S6, 19.3R3-S3, 19.4R1-S4, 19.4R3-S5, 20.1R2-S2, 20.1R3, 20.2R3-S1, 20.3R2-S1, 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-2021-31361?

    The severity of CVE-2021-31361 is classified as high, as it allows unauthorized users to impact the CPU utilization of affected devices.

  • How do I fix CVE-2021-31361?

    To fix CVE-2021-31361, it is recommended to apply the latest security patches provided by Juniper Networks for the affected Junos OS versions.

  • Which devices are affected by CVE-2021-31361?

    CVE-2021-31361 affects several devices including those in the Juniper QFX Series and PTX Series running specific vulnerable versions of Junos OS.

  • Can unauthorized access be used to exploit CVE-2021-31361?

    Yes, CVE-2021-31361 can be exploited by unauthenticated network-based attackers, which makes it a serious vulnerability.

  • What versions of Junos OS are impacted by CVE-2021-31361?

    CVE-2021-31361 impacts Junos OS versions 17.3, 17.4, 18.1, 18.2, 18.3, 18.4, 19.1, 19.2, 19.3, 19.4, and several variations thereof.

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