CVE-2025-52986 Junos OS and Junos OS Evolved: When RIB sharding is configured each time a show command is executed RPD memory leaks

Medium 6.8 Published Updated

A local low-privileged user can cause a denial of service by triggering memory leaks in the routing daemon when RIB sharding is enabled.

Exploited in the wild
Not known
Login needed
Any signed-in user
Attackable
Local or same network only
Victim action needed
Not needed
Fix
None listed

What is CVE-2025-52986?

CVE-2025-52986 is a medium-severity denial of service vulnerability in Juniper Junos, published on 11 Jul 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A Missing Release of Memory after Effective Lifetime vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a local, low privileged user to cause an impact to the availability of the device.

When RIB sharding is enabled and a user executes one of several routing related 'show' commands, a certain amount of memory is leaked. When all available memory has been consumed rpd will crash and restart.

The leak can be monitored with the CLI command:

show task memory detail | match task_shard_mgmt_cookie

where the allocated memory in bytes can be seen to continuously increase with each exploitation.

This issue affects:

Junos OS:

* all versions before 21.2R3-S9, * 21.4 versions before 21.4R3-S11, * 22.2 versions before 22.2R3-S7, * 22.4 versions before 22.4R3-S7, * 23.2 versions before 23.2R2-S4,  * 23.4 versions before 23.4R2-S4, * 24.2 versions before 24.2R2, * 24.4 versions before 24.4R1-S2, 24.4R2;

Junos OS Evolved:

* all versions before 22.2R3-S7-EVO * 22.4-EVO versions before 22.4R3-S7-EVO, * 23.2-EVO versions before 23.2R2-S4-EVO, * 23.4-EVO versions before 23.4R2-S4-EVO, * 24.2-EVO versions before 24.2R2-EVO,  * 24.4-EVO versions before 24.4R2-EVO.

Weakness: CWE-401

Which versions are affected by CVE-2025-52986?

It affects 2 products.

Products include Juniper Junos, Juniper Junos Os Evolved.

How do I fix CVE-2025-52986?

No fix has been published for CVE-2025-52986 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2025-52986 being exploited?

There is no known exploitation of CVE-2025-52986 in the wild and no public exploit code.

All Juniper Junos vulnerabilities

Sources

Also known as GHSA-mfrf-wpm5-gv78.

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