Junos OS (SRX firewalls)
CVE-2024-30380: l2cpd crash upon receipt of a specific TLV
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.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Junos OS 0 | 20.4R3-S9 or later |
| Junos OS 21.2 | 21.2R3-S7 or later |
| Junos OS 21.3 | 21.3R3-S5 or later |
| Junos OS 21.4 | 21.4R3-S4 or later |
| Junos OS 22.1 | 22.1R3-S4 or later |
| Junos OS 22.2 | 22.2R3-S2 or later |
| Junos OS 22.3 | 22.3R2-S2, 22.3R3-S1 or later |
| Junos OS 22.4 | 22.4R2-S2, 22.4R3 or later |
| Junos OS 23.2 | 23.2R1-S1, 23.2R2 or later |
| Junos OS Evolved 0 | 21.2R3-S7-EVO or later |
| Junos OS Evolved 21.3 | 21.3R3-S5-EVO or later |
| Junos OS Evolved 21.4 | 21.4R3-S5-EVO or later |
| Junos OS Evolved 22.1 | 22.1R3-S4-EVO or later |
| Junos OS Evolved 22.2 | 22.2R3-S2-EVO or later |
| Junos OS Evolved 22.3 | 22.3R2-S2-EVO, 22.3R3-S1-EVO or later |
| Junos OS Evolved 22.4 | 22.4R2-S2-EVO, 22.4R3-EVO or later |
| Junos OS Evolved 23.2 | 23.2R1-S1-EVO, 23.2R2-EVO or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
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.
Am I affected?
A sample configuration enabling LLDP is shown below:
[set protocols lldp interface all]
[set interfaces ge-0/0/0 lldp ...]
Workarounds
There are no known workarounds for this issue.
Exploitation
Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.