CVE-2024-30380: Juniper Junos

Medium severity, CVSS 6.5. EPSS: 0.3% chance of exploitation in the next 30 days.

An Improper Handling of Exceptional Conditions vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an adjacent unauthenticated attacker to cause a Denial of Service (DoS), which causes the l2cpd process to crash by sending a specific TLV. The l2cpd process is responsible for layer 2 control protocols, such as STP, RSTP, MSTP, VSTP, ERP, and LLDP.  The impact of the l2cpd crash is reinitialization of STP protocols (RSTP, MSTP or VSTP), and MVRP and ERP, leading to a Denial of Service.  Continued receipt and processing of this specific TLV will create a sustained Denial of Service (DoS) condition. This issue affects: Junos OS: all versions before 20.4R3-S9, from 21.2 before 21.2R3-S7, from 21.3 before 21.3R3-S5, from 21.4 before 21.4R3-S4, from 22.1 before 22.1R3-S4, from 22.2 before 22.2R3-S2, from 22.3 before 22.3R2-S2, 22.3R3-S1, from 22.4 before 22.4R2-S2, 22.4R3, from 23.2 before 23.2R1-S1, 23.2R2; Junos OS Evolved: all versions before 21.2R3-S7, from 21.3 before 21.3R3-S5-EVO, from 21.4 before 21.4R3-S5-EVO, from 22.1 before 22.1R3-S4-EVO, from 22.2 before 22.2R3-S2-EVO, from 22.3 before 22.3R2-S2-EVO, 22.3R3-S1-EVO, from 22.4 before 22.4R2-S2-EVO, 22.4R3-EVO, from 23.2 before 23.2R1-S1-EVO, 23.2R2-EVO.

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 2024-04-16. Last modified 2026-06-17.