CVE-2025-52961: An Uncontrolled Resource Consumption vulnerability in the Connectivity Fault Management (CFM) daemon and the Connectivity Fault Management Manager (cfmman) of J

An Uncontrolled Resource Consumption vulnerability in the Connectivity Fault Management (CFM) daemon and the Connectivity Fault Management Manager (cfmman) of J

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 node fpc0 detail | match cfmman F S UID PID PPID PGID SID C PRI NI ADDR SZ WCHAN RSS PSR STIME TTY TIME CMD 4 S root 15204 1 15204 15204 0

Description from the National Vulnerability Database, published by sirt@juniper.net

What it means for a small business

Junos OS Evolved is network equipment or remote-access software: the box between your office and the internet. These are a favorite target because breaking one opens the whole office.

If an IT provider set it up, ask them to confirm the firmware version and the date it was updated. If nobody looks after it, that's the bigger problem.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.48%, higher than 41% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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