An Improper Handling of Exceptional Conditions vulnerability in the broadband edge subscriber management daemon (bbe-smgd) of Juniper Networks Junos OS on MX Series allows an attacker directly connected to the vulnerable system who repeatedly flaps DHCP subscriber sessions to cause a slow memory leak, ultimately leading to a Denial of Service (DoS). Memory can only be recovered by manually restarting bbe-smgd. This issue only occurs if BFD liveness detection for DHCP subscribers is enabled. Systems without BFD liveness detection enabled are not vulnerable to this issue. Indication of the issue can be observed by periodically executing the 'show system processes extensive' command, which will indicate an increase in memory allocation for bbe-smgd. A small amount of memory is leaked every
The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S9, 21.2R3-S7, 21.3R3-S5, 21.4R3-S5, 22.1R3-S4, 22.2R3-S3, 22.3R3-S2, 22.4R2-S2, 22.4R3, 23.2R1-S1, 23.2R2, 23.4R1, and all subsequent releases.
This issue can be mitigated by disabling BFD liveness detection for DHCP subscribers. Service can be restored by manually restarting the bbe-smgd process periodically.
| Product | Vulnerable range | Fixed version | Advisory |
|---|---|---|---|
| Juniper Networks Junos OS | <20.4R3-S9 | 20.4R3-S9 | advisory ↗ |
| Juniper Networks Junos OS | >=21.2<21.2R3-S7 | 21.2R3-S7 | advisory ↗ |
| Juniper Networks Junos OS | >=21.3<21.3R3-S5 | 21.3R3-S5 | advisory ↗ |
| Juniper Networks Junos OS | >=21.4<21.4R3-S5 | 21.4R3-S5 | advisory ↗ |
| Juniper Networks Junos OS | >=22.1<22.1R3-S4 | 22.1R3-S4 | advisory ↗ |
| Juniper Networks Junos OS | >=22.2<22.2R3-S3 | 22.2R3-S3 | advisory ↗ |
| Juniper Networks Junos OS | >=22.3<22.3R3-S2 | 22.3R3-S2 | advisory ↗ |
| Juniper Networks Junos OS | >=22.4<22.4R2-S2, 22.4R3 | 22.4R2-S2, 22.4R3 | advisory ↗ |
| Juniper Networks Junos OS | >=23.2<23.2R1-S1, 23.2R2 | 23.2R1-S1, 23.2R2 | advisory ↗ |