CVE-2024-21595

Name: CVE-2024-21595
Creator: NVD / NIST
Published: 2024-01-12T01:15:47.063+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.54%

Last modified Jun 17, 2026

CVE-2024-21595 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. . EPSS estimates a 0.54% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.54%

41.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-1286

Affected Software

Vendor	Product	Versions	Update
Juniper	Junos	21.4	R3
Juniper	Junos	22.1	R3
Juniper	Junos	22.2	R2
Juniper	Junos	22.3	—
Juniper	Junos	22.4	—
Juniper	Junos	23.1	R1

References

https://advisory.juniper.net/JSA75734Vendor Advisory
https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NThird Party Advisory
https://advisory.juniper.net/JSA75734Vendor Advisory
https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NThird Party Advisory

Timeline

Published: Jan 12, 2024
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2024-21595?

How severe is CVE-2024-21595?

CVE-2024-21595 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.54% probability of exploitation in the next 30 days.

How do I fix CVE-2024-21595?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2024-21595?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST