CVE-2024-39531

/// Technical description

An Improper Handling of Values vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS Evolved on ACX 7000 Series allows a network-based, unauthenticated attacker to cause a Denial-of-Service (DoS).

If a value is configured for DDoS bandwidth or burst parameters for any protocol in

a queue, all protocols which share the same queue will have

their bandwidth or burst value changed to the new value. If, for example, OSPF was configured with a certain bandwidth value, ISIS would also be limited to this value. So inadvertently either the control plane is open for a high level of specific traffic which was supposed to be limited to a lower value, or the limit for a certain protocol is so low that chances to succeed with a volumetric DoS attack are significantly increased. 

This issue affects Junos OS Evolved on ACX 7000 Series:

* All versions before 21.4R3-S7-EVO,

* 22.1 versions before 22.1R3-S6-EVO, 

* 22.2 versions before 22.2R3-S3-EVO,

* 22.3

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References