CVE-2021-0285

Junos OS: QFX5000 Series and EX4600 Series: Continuous traffic destined to a device configured with MC-LAG leading to nodes losing their control connection which can impact traffic

HIGH

7.5

CVSS Score

Published: July 15, 2021 at 08:00 PM UTC

Updated: June 17, 2026 at 03:29 AM UTC

45 products affected across 2 vendorsJunosQfx5200Qfx5110

Using Junos OS by Juniper Networks?

Get instant alerts when new vulnerabilities affect Junos OS - before attackers find them.

Real-time alertsTrack your software stackFree plan available

Start Free Sign In

Severity

HIGH7.5

Exploit prediction

EPSS 1.0%

Description

An uncontrolled resource consumption vulnerability in Juniper Networks Junos OS on QFX5000 Series and EX4600 Series switches allows an attacker sending large amounts of legitimate traffic destined to the device to cause Interchassis Control Protocol (ICCP) interruptions, leading to an unstable control connection between the Multi-Chassis Link Aggregation Group (MC-LAG) nodes which can in turn lead to traffic loss. Continued receipt of this amount of traffic will create a sustained Denial of Service (DoS) condition. An indication that the system could be impacted by this issue is the following log message: "DDOS_PROTOCOL_VIOLATION_SET: Warning: Host-bound traffic for protocol/exception LOCALNH:aggregate exceeded its allowed bandwidth at fpc <fpc number> for <n> times, started at <timestamp>" This issue affects Juniper Networks Junos OS on QFX5000 Series and EX4600 Series: 15.1 versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S5; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R2-S8, 18.4R3-S7; 19.1 versions prior to 19.1R3-S5; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S2; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R2-S3, 20.2R3; 20.3 versions prior to 20.3R2; 20.4 versions prior to 20.4R1-S1, 20.4R2.

Affected

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

Junos · Juniper Networks

95%

15.1 ≤ v < 15.1R7-S917.3 ≤ v < 17.3R3-S1117.4 ≤ v < 17.4R2-S13, 17.4R3-S518.3 ≤ v < 18.3R3-S518.4 ≤ v < 18.4R2-S8, 18.4R3-S719.1 ≤ v < 19.1R3-S519.2 ≤ v < 19.2R1-S6, 19.2R3-S219.3 ≤ v < 19.3R2-S6, 19.3R3-S219.4 ≤ v < 19.4R1-S4, 19.4R2-S4, 19.4R3-S220.1 ≤ v < 20.1R2-S2, 20.1R320.2 ≤ v < 20.2R2-S3, 20.2R320.3 ≤ v < 20.3R220.4 ≤ v < 20.4R1-S1, 20.4R215.1 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 15.1 r7-s7 15.1 r7-s8 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-s10 17.3 r3-s2 17.3 r3-s3 17.3 r3-s4 17.3 r3-s5 17.3 r3-s6 17.3 r3-s7 17.3 r3-s8 17.3 r3-s9 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-s10 17.4 r2-s11 17.4 r2-s12 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 17.4 r3-s2 17.4 r3-s3 17.4 r3-s4 18.3 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 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 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 19.2 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 r2 19.2 r2-s1 19.2 r3 19.2 r3-s1 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 r3 19.3 r3-s1 19.4 19.4 r1 19.4 r1-s1 19.4 r1-s2 19.4 r1-s3 19.4 r2 19.4 r2-s1 19.4 r2-s2 19.4 r2-s3 19.4 r3 19.4 r3-s1 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 20.2 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 20.3 20.3 r1 20.3 r1-s1 20.4 20.4 r1

Affected range stops below 15.1R7-S9, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.3R3-S11, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.4R2-S13, 17.4R3-S5, 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 18.4R2-S8, 18.4R3-S7, so it looks safe — our inference, not a vendor statement

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

Affected range stops below 19.2R1-S6, 19.2R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R2-S6, 19.3R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.4R1-S4, 19.4R2-S4, 19.4R3-S2, so it looks safe — our inference, not a vendor statement

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

Affected range stops below 20.2R2-S3, 20.2R3, 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 20.4R1-S1, 20.4R2, so it looks safe — our inference, not a vendor statement

juniper-ex4200 (environment) · juniper-ex4200-vc (environment) · juniper-ex4300 (environment) · juniper-ex4300-24p (environment) · juniper-ex4300-24p-s (environment) · juniper-ex4300-24t (environment) · juniper-ex4300-24t-s (environment) · juniper-ex4300-32f (environment) · juniper-ex4300-32f-dc (environment) · juniper-ex4300-32f-s (environment) · juniper-ex4300-48mp (environment) · juniper-ex4300-48mp-s (environment) · juniper-ex4300-48p (environment) · juniper-ex4300-48p-s (environment) · juniper-ex4300-48t (environment) · juniper-ex4300-48t-afi (environment) · juniper-ex4300-48t-dc (environment) · juniper-ex4300-48t-dc-afi (environment) · juniper-ex4300-48t-s (environment) · juniper-ex4300-48tafi (environment) · juniper-ex4300-48tdc (environment) · juniper-ex4300-48tdc-afi (environment) · juniper-ex4300-mp (environment) · juniper-ex4300-vc (environment) · juniper-ex4300m (environment) · juniper-ex4400 (environment) · juniper-ex4500 (environment) · juniper-ex4500-vc (environment) · juniper-ex4550 (environment) · juniper-ex4550-vc (environment) · juniper-ex4600 (environment) · juniper-ex4600-vc (environment) · juniper-ex4650 (environment) · juniper-qfx5100 (environment) · juniper-qfx5100-96s (environment) · juniper-qfx5110 (environment) · juniper-qfx5120 (environment) · juniper-qfx5130 (environment) · juniper-qfx5200 (environment) · juniper-qfx5200-32c (environment) · juniper-qfx5200-48y (environment) · juniper-qfx5210 (environment) · juniper-qfx5210-64c (environment) · juniper-qfx5220 (environment)

Ex4200 · Juniperdevice

80%

All versions

Ex4200-Vc · Juniperdevice

80%

All versions

Ex4300 · Juniperdevice

80%

All versions

Ex4300-24P · Juniperdevice

80%

All versions