CVE-2024-39558

/// Technical description

An Unchecked Return Value vulnerability in the Routing Protocol Daemon (rpd) on Juniper Networks Junos OS and Juniper Networks Junos OS Evolved allows a logically adjacent, unauthenticated attacker sending a specific PIM packet to cause rpd to crash and restart, resulting in a Denial of Service (DoS), when PIM is configured with Multicast-only Fast Reroute (MoFRR). Continued receipt and processing of this packet may create a sustained Denial of Service (DoS) condition.

This issue is observed on Junos and Junos Evolved platforms where PIM is configured along with MoFRR. MoFRR tries to select the active path, but due to an internal timing issue, rpd is unable to select the forwarding next-hop towards the source, resulting in an rpd crash.

This issue affects:

Junos OS:

* All versions before 20.4R3-S10,

* from 21.2 before 21.2R3-S7,

* from 21.4 before 21.4R3-S6,

* from 22.1 before 22.1R3-S5,

* from 22.2 before 22.2R3-S3,

* from 22.3 before 22.3R3,

* from 22

/// 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