Junos OS: SRX 5000 Series: Repeated execution of a specific CLI command causes a flowd crash

A Heap-based Buffer Overflow vulnerability in the Network Services Daemon (NSD) of Juniper Networks Junos OS allows authenticated, low privileged, local attacker to cause a Denial of Service (DoS).

On an SRX 5000 Series device, when executing a specific command repeatedly, memory is corrupted, which leads to a Flow Processing Daemon (flowd) crash.

The NSD process has to be restarted to restore services.

If this issue occurs, it can be checked with the following command:

user@host> request security policies check
The following log message can also be observed:

Error: policies are out of sync for PFE node<number>.fpc<number>.pic<number>.
This issue affects:

Juniper Networks Junos OS on SRX 5000 Series

* All versions earlier than 20.4R3-S6;
* 21.1 versions earlier than 21.1R3-S5;
* 21.2 versions earlier than 21.2R3-S4;
* 21.3 versions earlier than 21.3R3-S3;
* 21.4 versions earlier than 21.4R3-S3;
* 22.1 versions earlier than 22.1R3-S1;
* 22.2 versions earlier than 22.2R3;
* 22.3 versions earlier than 22.3R2.