An Improper Handling of Exceptional Conditions vulnerability in the rpd-server of Juniper Networks Junos OS and Junos OS Evolved within cRPD allows an unauthenticated network-based attacker sending crafted TCP traffic to the routing engine (RE) to cause a CPU-based Denial of Service (DoS).
If specially crafted TCP traffic is received by the control plane, or a TCP session terminates unexpectedly, it will cause increased control plane CPU utilization by the rpd-server process.
While not explicitly required, the impact is more severe when RIB sharding is enabled.
Task accounting shows unexpected reads by the RPD Server jobs for shards:
user@junos> show task accounting detail ... read:RPD Server.0.0.0.0+780.192.168.0.78+48886 TOT:00000003.00379787 MAX:00000000.00080516 RUNS: 233888\ read:RPD Server.0.0.0.0+780.192.168.0.78+49144 TOT:00000004.00007565 MAX:00000000.00080360 RUNS: 233888\ read:RPD Server.0.0.0.0+780.192.168.0.78+49694 TOT:00000003.00600584 MAX:00000000.00080463 RUNS: 233888\ read:RPD Server.0.0.0.0+780.192.168.0.78+50246 TOT:00000004.00346998 MAX:00000000.00080338 RUNS: 233888\
This issue affects:
Junos OS with cRPD:
* All versions before 21.2R3-S8, * 21.4 before 21.4R3-S7, * 22.1 before 22.1R3-S6, * 22.2 before 22.2R3-S4, * 22.3 before 22.3R3-S3, * 22.4 before 22.4R3-S2, * 23.2 before 23.2R2-S2, * 24.2 before 24.2R2;
Junos OS Evolved with cRPD:
* All versions before 21.4R3-S7-EVO, * 22.2 before 22.2R3-S4-EVO, * 22.3 before 22.3R3-S3-EVO, * 22.4 before 22.4R3-S2-EVO, * 23.2 before 23.2R2-EVO.