SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2024-39547

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…

HIGH 8.7EPSS 0.97%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.97%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 4.0
8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.97% probability · 60th percentile
CISA KEV
Not listed
Weakness
CWE-755
Affected
juniper/junos containerized routing protocol daemon
Source
sirt@juniper.net

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.