Rapid7

vulnerability

Juniper Junos OS: 2024-01 Security Bulletin: Junos OS: EX4100, EX4400, EX4600 and QFX5000 Series: A high rate of specific ICMP traffic will cause the PFE to hang (JSA75734) (CVE-2024-21595)

Severity
8
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:C)
Published
Jan 10, 2024
Added
Jan 11, 2024
Modified
Mar 27, 2026

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.

Solution

juniper-junos-os-upgrade-latest
Title
Rapid7 Labs

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