CVE-2024-21595

Junos OS: EX4100, EX4400, EX4600, QFX5000 Series: A high rate of specific ICMP traffic will cause the PFE to hang

HIGH

7.5

CVSS Score

Published: January 12, 2024 at 12:52 AM UTC

Updated: June 17, 2026 at 07:09 AM UTC

16 products affected across 2 vendorsJunosQfx5200Qfx5110

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Severity

HIGH7.5

Exploit prediction

EPSS 0.5%

SSVC

No known exploit

Description

An Improper Validation of Syntactic Correctness of Input vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows a network-based, unauthenticated attacker to cause a Denial of Service (DoS). If an attacker sends high rate of specific ICMP traffic to a device with VXLAN configured, this causes a deadlock of the PFE and results in the device becoming unresponsive. A manual restart will be required to recover the device. This issue only affects EX4100, EX4400, EX4600, QFX5000 Series devices. This issue affects: Juniper Networks Junos OS * 21.4R3 versions earlier than 21.4R3-S4; * 22.1R3 versions earlier than 22.1R3-S3; * 22.2R2 versions earlier than 22.2R3-S1; * 22.3 versions earlier than 22.3R2-S2, 22.3R3; * 22.4 versions earlier than 22.4R2; * 23.1 versions earlier than 23.1R2.

Affected

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

Junos · Juniper Networks

95%

21.4R3 ≤ v < 21.4R3-S422.1R3 ≤ v < 22.1R3-S322.2R2 ≤ v < 22.2R3-S122.3 ≤ v < 22.3R2-S222.3 ≤ v < 22.3R2-S2, 22.3R322.3 ≤ v < 22.3R322.4 ≤ v < 22.4R223.1 ≤ v < 23.1R221.4 r3 21.4 r3-s1 21.4 r3-s2 21.4 r3-s3 21.4R3 22.1 r3 22.1 r3-s1 22.1 r3-s2 22.1R3 22.2 r2 22.2 r2-s1 22.2 r2-s2 22.2 r3 22.2R2 22.3 22.3 r1 22.3 r1-s1 22.3 r1-s2 22.3 r2 22.3 r2-s1 22.4 22.4 r1 22.4 r1-s1 22.4 r1-s2 23.1 23.1 r1

Affected range stops below 21.4R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.1R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.2R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.3R2-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.3R2-S2, 22.3R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.3R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.4R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 23.1R2, so it looks safe — our inference, not a vendor statement

juniper-ex4100 (environment) · juniper-ex4400 (environment) · juniper-ex4600 (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) · juniper-qfx5700 (environment)

Ex4100 · Juniperdevice

80%

All versions

Ex4400 · Juniperdevice

80%

All versions

Ex4600 · Juniperdevice

80%

All versions

Qfx5100 · Juniperdevice

80%

All versions