CVE-2025-52961

/// Technical description

An Uncontrolled Resource Consumption vulnerability in the Connectivity Fault Management (CFM) daemon and the Connectivity Fault Management Manager (cfmman) of Juniper Networks Junos OS Evolved on PTX10001-36MR, PTX10002-36QDD, PTX10004, PTX10008, PTX10016 allows an unauthenticated, adjacent attacker to cause a Denial-of-Service (DoS).

An attacker on an adjacent device sending specific valid traffic can cause cfmd to spike the CPU to 100% and cfmman's memory to leak, eventually to cause the FPC crash and restart.

Continued receipt and processes of these specific valid packets will sustain the Denial of Service (DoS) condition.

An indicator of compromise is to watch for an increase in cfmman memory rising over time by issuing the following command and evaluating the RSS number. If the RSS is growing into GBs then consider restarting the device to temporarily clear memory.

  user@device> show system processes node fpc<num> detail | match cfmman

Example: 

  show system processes no

/// 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