CVE-2024-21604

/// Technical description

An Allocation of Resources Without Limits or Throttling vulnerability in the kernel of Juniper Networks Junos OS Evolved allows an unauthenticated, network-based attacker to cause a Denial of Service (DoS).

If a high rate of specific valid packets are processed by the routing engine (RE) this will lead to a loss of connectivity of the RE with other components of the chassis and thereby a complete and persistent system outage. Please note that a carefully designed lo0 firewall filter will block or limit these packets which should prevent this issue from occurring.

The following log messages can be seen when this issue occurs:

<host> kernel: nf_conntrack: nf_conntrack: table full, dropping packet

This issue affects Juniper Networks Junos OS Evolved:

* All versions earlier than 20.4R3-S7-EVO;

* 21.2R1-EVO and later versions;

* 21.4-EVO versions earlier than 21.4R3-S5-EVO;

* 22.1-EVO versions earlier than 22.1R3-S2-EVO;

* 22.2-EVO versions earlier than 22.2R3-EVO;

*

/// 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