CVE-2024-39552: Juniper Junos

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

An Improper Handling of Exceptional Conditions vulnerability in the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows a network based, unauthenticated attacker to cause the RPD process to crash leading to a Denial of Service (DoS). When a malformed BGP UPDATE packet is received over an established BGP session, RPD crashes and restarts. Continuous receipt of the malformed BGP UPDATE messages will create a sustained Denial of Service (DoS) condition for impacted devices. This issue affects eBGP and iBGP, in both IPv4 and IPv6 implementations. This issue requires a remote attacker to have at least one established BGP session. This issue affects: Juniper Networks Junos OS: * All versions earlier than 20.4R3-S9; * 21.2 versions earlier than 21.2R3-S7; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S6; * 22.1 versions earlier than 22.1R3-S4; * 22.2 versions earlier than 22.2R3-S3; * 22.3 versions earlier than 22.3R3-S2; * 22.4 versions earlier than 22.4R3; * 23.2 versions earlier than 23.2R2. Juniper Networks Junos OS Evolved: * All versions earlier than 21.2R3-S7; * 21.3-EVO versions earlier than 21.3R3-S5; * 21.4-EVO versions earlier than 21.4R3-S8; * 22.1-EVO versions earlier than 22.1R3-S4; * 22.2-EVO versions earlier than 22.2R3-S3; * 22.3-EVO versions earlier than 22.3R3-S2; * 22.4-EVO versions earlier than 22.4R3; * 23.2-EVO versions earlier than 23.2R2.

Affected products

• Juniper Junos: before 20.4 (fixed in 20.4); version 20.4 only; version 21.2 only; version 21.3 only; version 21.4 only; version 22.1 only; …
• Juniper Junos OS Evolved: before 21.2 (fixed in 21.2); version 21.2 only; version 21.3 only; version 21.4 only; version 22.1 only; version 22.2 only; …

Published 2024-07-11. Last modified 2026-06-17.