CVE-2024-21595

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

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.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 21.4R3-S4, 22.1R3-S3, 22.2R3-S1, 22.3R2-S2, 22.3R3, 22.4R2, 23.1R2, 23.2R1, and all subsequent releases.

Workaround:

  • There are no known workarounds for this issue.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.15%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://advisory.juniper.net/JSA75734 vendor 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:N third party advisory technical description

Frequently Asked Questions

What is the severity of CVE-2024-21595?
CVE-2024-21595 has been scored as a high severity vulnerability.
How to fix CVE-2024-21595?
To fix CVE-2024-21595: The following software releases have been updated to resolve this specific issue: Junos OS 21.4R3-S4, 22.1R3-S3, 22.2R3-S1, 22.3R2-S2, 22.3R3, 22.4R2, 23.1R2, 23.2R1, and all subsequent releases.
Is CVE-2024-21595 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-21595 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2024-21595?
CVE-2024-21595 affects Juniper Networks Junos OS.
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