The Juniper router configured for MSDP must limit the amount of source-active messages it accepts on per-peer basis.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-253981 | JUEX-RT-000090 | SV-253981r843976_rule | Low |
| Description |
| To reduce any risk of a denial-of-service (DoS) attack from a rogue or misconfigured MSDP router, the router must be configured to limit the number of source-active messages it accepts from each peer. |
| STIG | Date |
| Juniper EX Series Switches Router Security Technical Implementation Guide | 2024-06-10 |
Details
| Check Text (C-57433r843974_chk) |
| Review the router configuration to determine if it is configured to limit the amount of source-active messages it accepts on a per-peer basis. [edit protocols] msdp { active-source-limit { maximum <1..1000000>; threshold <1..1000000>; log-warning <percent to log warning>; } local-address <lo0 address>; <additional configuration> peer <address> { active-source-limit { maximum <1..1000000>; threshold <1..1000000>; log-warning <percent to log warning>; } authentication-key "hashed PSK"; ## SECRET-DATA } } Note: Both the global, and the peer limit, are applied to every MSDP peer, and Junos applies the most restrictive limit. The maximum value sets the upper limit for source-active messages and the threshold value determines when Junos begins Random Early Detection (RED) dropping to alleviate congestion. The log-warning value is a percent where Junos begins generating syslog messages. If the router is not configured to limit the source-active messages it accepts, this is a finding. |
| Fix Text (F-57384r843975_fix) |
| Configure the MSDP router to limit the amount of source-active messages it accepts from each peer. set protocols msdp active-source-limit maximum <1..1000000> set protocols msdp active-source-limit threshold <1..1000000> set protocols msdp active-source-limit log-warning <percent to log warning> <additional configuration> set protocols msdp peer <address> active-source-limit maximum <1..1000000> set protocols msdp peer <address> active-source-limit threshold <1..1000000> set protocols msdp peer <address> active-source-limit log-warning <percent to log warning> |