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

MEDIUM

6.5

CVSS Score

Published: October 19, 2021 at 06:16 PM UTC

Updated: June 17, 2026 at 03:51 AM UTC

5 products affected across 2 vendorsJunosEx2300Ex3400

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Severity

MEDIUM6.5

Exploit prediction

EPSS 0.4%

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Junos · Juniper Networks

95%

v < 15.1v < 15.1R7-S7v < 18.1v < 18.1R3-S12v < 18.3v < 18.3R3-S516.1 ≤ v < 16.1R7-S817.1 ≤ v < 17.1R2-S1217.2 ≤ v < 17.2R3-S417.3 ≤ v < 17.3R3-S817.4 ≤ v < 17.4R2-S10, 17.4R3-S218.1 ≤ v < 18.1R3-S1018.2 ≤ v < 18.2R2-S7, 18.2R3-S318.2 ≤ v < 18.2R3-S718.3 ≤ v < 18.3R2-S4, 18.3R3-S218.3 ≤ v < 18.3R3-S418.4 ≤ v < 18.4R1-S7, 18.4R2-S4, 18.4R3-S118.4 ≤ v < 18.4R2-S9, 18.4R3-S718.4 ≤ v < 18.4R2-S9, 18.4R3-S919.1 ≤ v < 19.1R1-S5, 19.1R2-S1, 19.1R319.1 ≤ v < 19.1R2-S3, 19.1R3-S419.1 ≤ v < 19.1R2-S3, 19.1R3-S619.2 ≤ v < 19.2R1-S5, 19.2R219.2 ≤ v < 19.2R1-S7, 19.2R3-S319.2 ≤ v < 19.2R3-S119.3 ≤ v < 19.3R2-S2, 19.3R319.3 ≤ v < 19.3R2-S7, 19.3R3-S319.3 ≤ v < 19.3R3-S119.4 ≤ v < 19.4R1-S2, 19.4R219.4 ≤ v < 19.4R3-S119.4 ≤ v < 19.4R3-S520.1 ≤ v < 20.1R2-S2, 20.1R3-S120.1 ≤ v < 20.1R320.2 ≤ v < 20.2R320.2 ≤ v < 20.2R3-S220.3 ≤ v < 20.3R220.3 ≤ v < 20.3R3-S120.4 ≤ v < 20.4R2-S1, 20.4R321.1 ≤ v < 21.1R215.1 15.1 a1 15.1 f 15.1 f1 15.1 f2 15.1 f2-s1 15.1 f2-s2 15.1 f2-s3 15.1 f2-s4 15.1 f3 15.1 f4 15.1 f5 15.1 f5-s7 15.1 f6 15.1 f6-s1 15.1 f6-s10 15.1 f6-s12 15.1 f6-s2 15.1 f6-s3 15.1 f6-s4 15.1 f6-s5 15.1 f6-s6 15.1 f6-s7 15.1 f6-s8 15.1 f6-s9 15.1 f7 15.1 r 15.1 r1 15.1 r2 15.1 r3 15.1 r4 15.1 r4-s7 15.1 r4-s8 15.1 r4-s9 15.1 r5 15.1 r5-s1 15.1 r5-s3 15.1 r5-s5 15.1 r5-s6 15.1 r6 15.1 r6-s1 15.1 r6-s2 15.1 r6-s3 15.1 r6-s4 15.1 r6-s6 15.1 r7 15.1 r7-s1 15.1 r7-s2 15.1 r7-s3 15.1 r7-s4 15.1 r7-s5 15.1 r7-s6 16.1 16.1 r 16.1 r1 16.1 r2 16.1 r3 16.1 r3-s10 16.1 r3-s11 16.1 r3-s8 16.1 r4 16.1 r4-s12 16.1 r4-s2 16.1 r4-s3 16.1 r4-s4 16.1 r4-s6 16.1 r4-s8 16.1 r4-s9 16.1 r5 16.1 r5-s4 16.1 r6 16.1 r6-s1 16.1 r6-s3 16.1 r6-s4 16.1 r6-s6 16.1 r7 16.1 r7-s2 16.1 r7-s3 16.1 r7-s4 16.1 r7-s5 16.1 r7-s6 16.1 r7-s7 17.1 17.1 r1 17.1 r1-s7 17.1 r2 17.1 r2-s1 17.1 r2-s10 17.1 r2-s11 17.1 r2-s2 17.1 r2-s3 17.1 r2-s4 17.1 r2-s5 17.1 r2-s6 17.1 r2-s7 17.1 r2-s8 17.1 r2-s9 17.2 17.2 r1 17.2 r1-s1 17.2 r1-s2 17.2 r1-s3 17.2 r1-s4 17.2 r1-s5 17.2 r1-s6 17.2 r1-s7 17.2 r1-s8 17.2 r2 17.2 r2-s11 17.2 r2-s4 17.2 r2-s6 17.2 r2-s7 17.2 r3 17.2 r3-s1 17.2 r3-s2 17.2 r3-s3 17.3 17.3 r1 17.3 r1-s1 17.3 r1-s4 17.3 r2 17.3 r2-s1 17.3 r2-s2 17.3 r2-s3 17.3 r2-s4 17.3 r2-s5 17.3 r3 17.3 r3-s1 17.3 r3-s2 17.3 r3-s3 17.3 r3-s4 17.3 r3-s5 17.3 r3-s6 17.3 r3-s7 17.4 17.4 r1 17.4 r1-s1 17.4 r1-s2 17.4 r1-s3 17.4 r1-s4 17.4 r1-s5 17.4 r1-s6 17.4 r1-s7 17.4 r2 17.4 r2-s1 17.4 r2-s2 17.4 r2-s3 17.4 r2-s4 17.4 r2-s5 17.4 r2-s6 17.4 r2-s7 17.4 r2-s8 17.4 r2-s9 17.4 r3 17.4 r3-s1 18.1 18.1 r 18.1 r1 18.1 r2 18.1 r2-s1 18.1 r2-s2 18.1 r2-s4 18.1 r3 18.1 r3-s1 18.1 r3-s10 18.1 r3-s11 18.1 r3-s2 18.1 r3-s3 18.1 r3-s4 18.1 r3-s5 18.1 r3-s6 18.1 r3-s7 18.1 r3-s8 18.1 r3-s9 18.2 18.2 r 18.2 r1 18.2 r1-s2 18.2 r1-s3 18.2 r1-s4 18.2 r1-s5 18.2 r2 18.2 r2-s1 18.2 r2-s2 18.2 r2-s3 18.2 r2-s4 18.2 r2-s5 18.2 r2-s6 18.2 r2-s7 18.2 r2-s8 18.2 r3 18.2 r3-s1 18.2 r3-s2 18.2 r3-s3 18.2 r3-s4 18.2 r3-s5 18.2 r3-s6 18.3 18.3 r 18.3 r1 18.3 r1-s1 18.3 r1-s2 18.3 r1-s3 18.3 r1-s4 18.3 r1-s5 18.3 r1-s6 18.3 r2 18.3 r2-s1 18.3 r2-s2 18.3 r2-s3 18.3 r2-s4 18.3 r3 18.3 r3-s1 18.3 r3-s2 18.3 r3-s3 18.3 r3-s4 18.4 18.4 r1 18.4 r1-s1 18.4 r1-s2 18.4 r1-s3 18.4 r1-s4 18.4 r1-s5 18.4 r1-s6 18.4 r1-s7 18.4 r2 18.4 r2-s1 18.4 r2-s2 18.4 r2-s3 18.4 r2-s4 18.4 r2-s5 18.4 r2-s6 18.4 r2-s7 18.4 r2-s8 18.4 r3 18.4 r3-s1 18.4 r3-s2 18.4 r3-s3 18.4 r3-s4 18.4 r3-s5 18.4 r3-s6 18.4 r3-s7 18.4 r3-s8 19.1 19.1 r1 19.1 r1-s1 19.1 r1-s2 19.1 r1-s3 19.1 r1-s4 19.1 r1-s5 19.1 r1-s6 19.1 r2 19.1 r2-s1 19.1 r2-s2 19.1 r3 19.1 r3-s1 19.1 r3-s2 19.1 r3-s3 19.1 r3-s4 19.1 r3-s5 19.2 19.2 r1 19.2 r1-s1 19.2 r1-s2 19.2 r1-s3 19.2 r1-s4 19.2 r1-s5 19.2 r1-s6 19.2 r1-s7 19.2 r2 19.2 r2-s1 19.2 r3 19.2 r3-s1 19.2 r3-s2 19.3 19.3 r1 19.3 r1-s1 19.3 r2 19.3 r2-s1 19.3 r2-s2 19.3 r2-s3 19.3 r2-s4 19.3 r2-s5 19.3 r2-s6 19.3 r3 19.3 r3-s1 19.3 r3-s2 19.4 19.4 r1 19.4 r1-s1 19.4 r1-s2 19.4 r1-s3 19.4 r1-s4 19.4 r2 19.4 r2-s1 19.4 r2-s2 19.4 r2-s3 19.4 r2-s4 19.4 r2-s5 19.4 r3 19.4 r3-s1 19.4 r3-s2 19.4 r3-s3 19.4 r3-s4 20.1 20.1 r1 20.1 r1-s1 20.1 r1-s2 20.1 r1-s3 20.1 r1-s4 20.1 r2 20.1 r2-s1 20.1 r2-s2 20.1 r3 20.2 20.2 r1 20.2 r1-s1 20.2 r1-s2 20.2 r1-s3 20.2 r2 20.2 r2-s1 20.2 r2-s2 20.2 r2-s3 20.2 r3 20.2 r3-s1 20.3 20.3 r1 20.3 r1-s1 20.3 r2 20.3 r2-s1 20.3 r3 20.4 20.4 r1 20.4 r1-s1 20.4 r2 21.1 21.1 r1 21.1 r1-s1

Affected range stops below 15.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 15.1R7-S7, so it looks safe — our inference, not a vendor statement

Affected range stops below 16.1R7-S8, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.1R2-S12, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.2R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.3R3-S8, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.4R2-S10, 17.4R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.1R3-S10, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.1R3-S12, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.2R2-S7, 18.2R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.2R3-S7, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.3, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.3R2-S4, 18.3R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.3R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.3R3-S5, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.4R1-S7, 18.4R2-S4, 18.4R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.4R2-S9, 18.4R3-S7, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.4R2-S9, 18.4R3-S9, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.1R1-S5, 19.1R2-S1, 19.1R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.1R2-S3, 19.1R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.1R2-S3, 19.1R3-S6, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.2R1-S5, 19.2R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.2R1-S7, 19.2R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.2R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R2-S2, 19.3R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R2-S7, 19.3R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.4R1-S2, 19.4R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.4R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.4R3-S5, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.1R2-S2, 20.1R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.1R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.2R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.2R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.3R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.3R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.4R2-S1, 20.4R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.1R2, so it looks safe — our inference, not a vendor statement

juniper-ex2300 (environment) · juniper-ex3400 (environment) · juniper-ex4300 (environment) · juniper-ex4300-mp (environment)

Ex2300 · Juniperdevice

80%

All versions

Ex3400 · Juniperdevice

80%

All versions

Ex4300 · Juniperdevice

80%

All versions

Ex4300-Mp · Juniperdevice

80%

All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://kb.juniper.net/JSA11227

References (1)

x_refsource_CONFIRMVendor Advisory

Source: [email protected]

https://kb.juniper.net/JSA11227

CVSS

6.5MEDIUMjuniper

Attack Vector: ADJACENT_NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: NONE
Integrity: NONE
Availability: HIGH

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-400

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