medium
6.5
CWE
400
Advisory Published
Updated

CVE-2021-31365: Junos OS: EX2300, EX3400 and EX4300 Series: An Aggregated Ethernet (AE) interface will go down due to a stream of specific layer 2 frames

First published: Tue Oct 19 2021(Updated: )

An Uncontrolled Resource Consumption vulnerability in Juniper Networks Junos OS on EX2300, EX3400 and EX4300 Series platforms allows an adjacent attacker sending a stream of layer 2 frames will trigger an Aggregated Ethernet (AE) interface to go down and thereby causing a Denial of Service (DoS). By continuously sending a stream of specific layer 2 frames an attacker will sustain the Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS EX4300 Series All versions prior to 15.1R7-S7; 16.1 versions prior to 16.1R7-S8; 17.1 versions prior to 17.1R2-S12; 17.2 versions prior to 17.2R3-S4; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S10, 17.4R3-S2; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R2-S7, 18.2R3-S3; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R1-S7, 18.4R2-S4, 18.4R3-S1; 19.1 versions prior to 19.1R1-S5, 19.1R2-S1, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S2, 19.3R3; 19.4 versions prior to 19.4R1-S2, 19.4R2. Juniper Networks Junos OS EX3400 and EX4300-MP Series All versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R2-S9, 18.4R3-S7; 19.1 versions prior to 19.1R2-S3, 19.1R3-S4; 19.2 versions prior to 19.2R3-S1; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R3-S1; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R3; 20.3 versions prior to 20.3R2. Juniper Networks Junos OS EX2300 Series All versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R2-S9, 18.4R3-S9; 19.1 versions prior to 19.1R2-S3, 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-S1; 20.4 versions prior to 20.4R2-S1, 20.4R3; 21.1 versions prior to 21.1R2.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper Junos<18.1
Juniper Junos=18.1
Juniper Junos=18.1-r
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-r
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-r2-s8
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-r
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-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=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=19.2
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-r1-s7
Juniper Junos=19.2-r2
Juniper Junos=19.2-r2-s1
Juniper Junos=19.2-r3
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-r2-s3
Juniper Junos=19.4-r2-s4
Juniper Junos=19.4-r2-s5
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=20.1-r2
Juniper Junos=20.1-r2-s1
Juniper Junos=20.1-r2-s2
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=20.3-r1
Juniper Junos=20.3-r1-s1
Juniper EX3400
Juniper EX4300
Juniper Junos<15.1
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=16.1
Juniper Junos=16.1-r
Juniper Junos=16.1-r1
Juniper Junos=16.1-r2
Juniper Junos=16.1-r3
Juniper Junos=16.1-r3-s10
Juniper Junos=16.1-r3-s11
Juniper Junos=16.1-r3-s8
Juniper Junos=16.1-r4
Juniper Junos=16.1-r4-s12
Juniper Junos=16.1-r4-s2
Juniper Junos=16.1-r4-s3
Juniper Junos=16.1-r4-s4
Juniper Junos=16.1-r4-s6
Juniper Junos=16.1-r4-s8
Juniper Junos=16.1-r4-s9
Juniper Junos=16.1-r5
Juniper Junos=16.1-r5-s4
Juniper Junos=16.1-r6
Juniper Junos=16.1-r6-s1
Juniper Junos=16.1-r6-s3
Juniper Junos=16.1-r6-s4
Juniper Junos=16.1-r6-s6
Juniper Junos=16.1-r7
Juniper Junos=16.1-r7-s2
Juniper Junos=16.1-r7-s3
Juniper Junos=16.1-r7-s4
Juniper Junos=16.1-r7-s5
Juniper Junos=16.1-r7-s6
Juniper Junos=16.1-r7-s7
Juniper Junos=17.1
Juniper Junos=17.1-r1
Juniper Junos=17.1-r1-s7
Juniper Junos=17.1-r2
Juniper Junos=17.1-r2-s1
Juniper Junos=17.1-r2-s10
Juniper Junos=17.1-r2-s11
Juniper Junos=17.1-r2-s2
Juniper Junos=17.1-r2-s3
Juniper Junos=17.1-r2-s4
Juniper Junos=17.1-r2-s5
Juniper Junos=17.1-r2-s6
Juniper Junos=17.1-r2-s7
Juniper Junos=17.1-r2-s8
Juniper Junos=17.1-r2-s9
Juniper Junos=17.2
Juniper Junos=17.2-r1
Juniper Junos=17.2-r1-s1
Juniper Junos=17.2-r1-s2
Juniper Junos=17.2-r1-s3
Juniper Junos=17.2-r1-s4
Juniper Junos=17.2-r1-s5
Juniper Junos=17.2-r1-s6
Juniper Junos=17.2-r1-s7
Juniper Junos=17.2-r1-s8
Juniper Junos=17.2-r2
Juniper Junos=17.2-r2-s11
Juniper Junos=17.2-r2-s4
Juniper Junos=17.2-r2-s6
Juniper Junos=17.2-r2-s7
Juniper Junos=17.2-r3
Juniper Junos=17.2-r3-s1
Juniper Junos=17.2-r3-s2
Juniper Junos=17.2-r3-s3
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-s1
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=17.4
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-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 EX4300-24T
Juniper Junos<18.3
Juniper Junos=18.3-r3-s4
Juniper Junos=18.4-r3-s7
Juniper Junos=18.4-r3-s8
Juniper Junos=19.1-r3-s4
Juniper Junos=19.1-r3-s5
Juniper Junos=19.2-r3-s1
Juniper Junos=19.2-r3-s2
Juniper Junos=19.3-r3-s1
Juniper Junos=19.3-r3-s2
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-r3
Juniper Junos=20.2-r3
Juniper Junos=20.2-r3-s1
Juniper Junos=20.3-r2
Juniper Junos=20.3-r2-s1
Juniper Junos=20.3-r3
Juniper Junos=20.4-r1
Juniper Junos=20.4-r1-s1
Juniper Junos=20.4-r2
Juniper Junos=21.1-r1
Juniper Junos=21.1-r1-s1
Juniper EX2300-24T

Remedy

The following software releases have been updated to resolve this specific issue in Junos OS - For EX4300 Series: 15.1R7-S7, 16.1R7-S8, 17.1R2-S12, 17.2R3-S4, 17.3R3-S8, 17.4R2-S10, 17.4R3-S2, 18.1R3-S10, 18.2R2-S7, 18.2R3-S3, 18.3R2-S4, 18.3R3-S2, 18.4R1-S7, 18.4R2-S4, 18.4R3-S1, 19.1R1-S5, 19.1R2-S1, 19.1R3, 19.2R2, 19.3R2-S2, 19.3R3, 19.4R1-S2, 19.4R2, 20.1R1, and all subsequent releases. - For EX3400 and EX4300-MP Series: 18.1R3-S12, 18.2R3-S7, 18.3R3-S4, 18.4R2-S9, 18.4R3-S7, 19.1R2-S3, 19.1R3-S4, 19.2R3-S1, 19.3R3-S1, 19.4R3-S1, 20.1R3, 20.2R3, 20.3R2, 20.4R1, and all subsequent releases. -For EX2300 Series: 18.3R3-S5, 18.4R2-S9, 18.4R3-S9, 19.1R2-S3, 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-S1, 20.4R2-S1, 20.4R3, 21.1R2, 21.2R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-31365?

    CVE-2021-31365 has a medium severity level due to its potential to cause denial of service.

  • How do I fix CVE-2021-31365?

    To fix CVE-2021-31365, upgrade to a non-vulnerable version of Junos OS as specified in the vendor's advisory.

  • What is the impact of CVE-2021-31365?

    The impact of CVE-2021-31365 includes the ability for an adjacent attacker to cause an Aggregated Ethernet interface to go down.

  • Which Juniper products are affected by CVE-2021-31365?

    CVE-2021-31365 affects Juniper Networks Junos OS on EX2300, EX3400, and EX4300 Series platforms.

  • Is there a workaround for CVE-2021-31365?

    Currently, no specific workarounds for CVE-2021-31365 are provided, and the recommended action is to apply the relevant updates.

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