Junos OS: SRX Series: On devices with Anti-Virus enabled, malicious server responses will cause memory to leak ultimately causing forwarding to stop

A Missing Release of Memory after Effective Lifetime vulnerability in the Anti-Virus processing of Juniper Networks Junos OS on SRX Series

allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).

On all SRX platforms with Anti-Virus enabled, if a server sends specific content in the HTTP body of a response to a client request, these packets are queued by Anti-Virus processing in Juniper Buffers (jbufs) which are never released. When these jbufs are exhausted, the device stops forwarding all transit traffic.

A jbuf memory leak can be noticed from the following logs:

(<node>.)<fpc> Warning: jbuf pool id <#> utilization level (<current level>%) is above <threshold>%!

To recover from this issue, the affected device needs to be manually rebooted to free the leaked jbufs.

This issue affects Junos OS on SRX Series: 

* all versions before 21.2R3-S9,
* 21.4 versions before 21.4R3-S10,
* 22.2 versions before 22.2R3-S6,
* 22.4 versions before 22.4R3-S6,
* 23.2 versions before 23.2R2-S3,
* 23.4 versions before 23.4R2-S3,
* 24.2 versions before 24.2R2.