On Juniper Networks Junos OS devices, a stream of TCP packets sent to the Routing Engine (RE) may cause mbuf leak which can lead to Flexible PIC Concentrator (FPC) crash or the system to crash and restart (vmcore). This issue can be trigged by IPv4 or IPv6 and it is caused only by TCP packets. This issue is not related to any specific configuration and it affects Junos OS releases starting from 17.4R1. However, this issue does not affect Junos OS releases prior to 18.2R1 when Nonstop active routing (NSR) is configured [edit routing-options nonstop-routing]. The number of mbufs is platform dependent. The following command provides the number of mbufs counter that are currently in use and maximum number of mbufs that can be allocated on a platform: user@host> show system buffers 2437/3143/55
The following software releases have been updated to resolve this specific issue: 17.4R2-S11, 17.4R3-S2, 18.1R3-S10, 18.2R2-S7, 18.2R3-S5, 18.2X75-D41, 18.2X75-D420.12, 18.2X75-D51, 18.2X75-D60, 18.2X75-D34, 18.3R2-S4, 18.3R3-S2, 18.4R1-S7, 18.4R2-S4, 18.4R3-S1, 19.1R1-S5, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S3, 19.3R3, 19.4R1-S2, 19.4R2, 20.1R1, and all subsequent releases.
There are no viable workarounds for this issue, however having the DDoS feature enabled and using the firewall filter to limit incoming packet towards the RE only from trusted networks and host help to mitigate this issue. The following command can be used to check if DDoS feature is enabled: user@host> show ddos-protection statistics DDOS protection global statistics: Policing on routing engine: Yes <--- must be "Yes" Policing on FPC: Yes Flow detection: Yes <-- must be Yes <snip>
| Product | Vulnerable range | Fixed version | Advisory |
|---|---|---|---|
| Juniper Networks Junos OS | >=17.4<17.4R2-S11, 17.4R3-S2 | 17.4R2-S11, 17.4R3-S2 | advisory ↗ |
| Juniper Networks Junos OS | >=18.1<18.1R3-S10 | 18.1R3-S10 | advisory ↗ |
| Juniper Networks Junos OS | >=18.2<18.2R2-S7, 18.2R3-S5 | 18.2R2-S7, 18.2R3-S5 | advisory ↗ |
| Juniper Networks Junos OS | >=18.2X75<18.2X75-D41, 18.2X75-D420.12, 18.2X75-D51, 18.2X75-D60, 18.2X75-D34 | 18.2X75-D41, 18.2X75-D420.12, 18.2X75-D51, 18.2X75-D60, 18.2X75-D34 | advisory ↗ |
| Juniper Networks Junos OS | >=18.3<18.3R2-S4, 18.3R3-S2 | 18.3R2-S4, 18.3R3-S2 | advisory ↗ |
| Juniper Networks Junos OS | >=18.4<18.4R1-S7, 18.4R2-S4, 18.4R3-S1 | 18.4R1-S7, 18.4R2-S4, 18.4R3-S1 | advisory ↗ |
| Juniper Networks Junos OS | >=19.1<19.1R1-S5, 19.1R2-S1, 19.1R3 | 19.1R1-S5, 19.1R2-S1, 19.1R3 | advisory ↗ |
| Juniper Networks Junos OS | >=19.2<19.2R1-S5, 19.2R2 | 19.2R1-S5, 19.2R2 | advisory ↗ |
| Juniper Networks Junos OS | >=19.3<19.3R2-S3, 19.3R3 | 19.3R2-S3, 19.3R3 | advisory ↗ |
| Juniper Networks Junos OS | >=19.4<19.4R1-S2, 19.4R2 | 19.4R1-S2, 19.4R2 | advisory ↗ |