CVE-2024-21603

/// Technical description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the kernel of Juniper Network Junos OS on MX Series allows a network based attacker with low privileges to cause a denial of service.

If a scaled configuration for Source class usage (SCU) / destination class usage (DCU) (more than 10 route classes) is present and the SCU/DCU statistics are gathered by executing specific SNMP requests or CLI commands, a 'vmcore' for the RE kernel will be seen which leads to a device restart. Continued exploitation of this issue will lead to a sustained DoS.

This issue only affects MX Series devices with MPC10, MPC11 or LC9600, and MX304. No other MX Series devices are affected.

This issue affects Juniper Networks Junos OS:

* All versions earlier than 20.4R3-S9;

* 21.2 versions earlier than 21.2R3-S6;

* 21.3 versions earlier than 21.3R3-S5;

* 21.4 versions earlier than 21.4R3;

* 22.1 versions earlier than 22.1R3;

* 22.2 versions earlier than 22.2R2;

* 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