CVE-2020-1668

Junos OS: EX2300 Series: High CPU load due to receipt of specific multicast packets on layer 2 interface

MEDIUM

6.5

CVSS Score

Published: October 16, 2020 at 08:31 PM UTC

Updated: June 17, 2026 at 03:02 AM UTC

2 products affected across 2 vendorsJunosEx2300

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Severity

MEDIUM6.5

Exploit prediction

EPSS 0.5%

Description

On Juniper Networks EX2300 Series, receipt of a stream of specific multicast packets by the layer2 interface can cause high CPU load, which could lead to traffic interruption. This issue occurs when multicast packets are received by the layer 2 interface. To check if the device has high CPU load due to this issue, the administrator can issue the following command: user@host> show chassis routing-engine Routing Engine status: ... Idle 2 percent the "Idle" value shows as low (2 % in the example above), and also the following command: user@host> show system processes summary ... PID USERNAME PRI NICE SIZE RES STATE TIME WCPU COMMAND 11639 root 52 0 283M 11296K select 12:15 44.97% eventd 11803 root 81 0 719M 239M RUN 251:12 31.98% fxpc{fxpc} the eventd and the fxpc processes might use higher WCPU percentage (respectively 44.97% and 31.98% in the above example). This issue affects Juniper Networks Junos OS on EX2300 Series: 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S5; 18.3 versions prior to 18.3R2-S4, 18.3R3-S3; 18.4 versions prior to 18.4R2-S5, 18.4R3-S4; 19.1 versions prior to 19.1R3-S2; 19.2 versions prior to 19.2R1-S5, 19.2R3; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2-S1, 19.4R3; 20.1 versions prior to 20.1R1-S2, 20.1R2.

Affected

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

Junos · Juniper Networks

95%

18.1 ≤ v < 18.1R3-S1118.2 ≤ v < 18.2R3-S518.3 ≤ v < 18.3R2-S4, 18.3R3-S318.4 ≤ v < 18.4R2-S5, 18.4R3-S419.1 ≤ v < 19.1R3-S219.2 ≤ v < 19.2R1-S5, 19.2R319.3 ≤ v < 19.3R2-S4, 19.3R319.4 ≤ v < 19.4R1-S3, 19.4R2-S1, 19.4R320.1 ≤ v < 20.1R1-S2, 20.1R218.1 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-s2 18.1 r3-s3 18.1 r3-s4 18.1 r3-s6 18.1 r3-s7 18.1 r3-s8 18.1 r3-s9 18.2 18.2 r1 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 r3 18.2 r3-s1 18.2 r3-s2 18.2 r3-s3 18.2 r3-s4 18.3 18.3 r1 18.3 r1-s1 18.3 r1-s2 18.3 r1-s3 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 r3 18.3 r3-s1 18.3 r3-s2 18.4 18.4 r1 18.4 r1-s1 18.4 r1-s2 18.4 r1-s5 18.4 r1-s6 18.4 r2 18.4 r2-s1 18.4 r2-s2 18.4 r2-s3 18.4 r2-s4 18.4 r3 18.4 r3-s1 18.4 r3-s2 18.4 r3-s3 19.1 19.1 r1 19.1 r1-s1 19.1 r1-s2 19.1 r1-s3 19.1 r1-s4 19.1 r2 19.1 r2-s1 19.1 r3 19.1 r3-s1 19.2 19.2 r1 19.2 r1-s1 19.2 r1-s2 19.2 r1-s3 19.2 r1-s4 19.3 19.3 r1 19.3 r1-s1 19.3 r2 19.3 r2-s1 19.3 r2-s2 19.3 r2-s3 19.4 19.4 r1 19.4 r1-s1 19.4 r1-s2 19.4 r2 20.1 20.1 r1 20.1 r1-s1

Affected range stops below 18.1R3-S11, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.2R3-S5, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.3R2-S4, 18.3R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.4R2-S5, 18.4R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.1R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.2R1-S5, 19.2R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R2-S4, 19.3R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.4R1-S3, 19.4R2-S1, 19.4R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.1R1-S2, 20.1R2, so it looks safe — our inference, not a vendor statement

juniper-ex2300 (environment)

Ex2300 · 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/JSA11065

References (1)

x_refsource_CONFIRMVendor Advisory

Source: [email protected]

https://kb.juniper.net/JSA11065

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-400NVD-CWE-noinfo

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