CVE-2024-21618

Junos OS and Junos OS Evolved: When LLDP is enabled and a malformed LLDP packet is received, l2cpd crashes

Description

An Access of Memory Location After End of Buffer vulnerability in the Layer-2 Control Protocols Daemon (l2cpd) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker to cause Denial of Service (DoS). On all Junos OS and Junos OS Evolved platforms, when LLDP is enabled on a specific interface, and a malformed LLDP packet is received, l2cpd crashes and restarts. The impact of the l2cpd crash is reinitialization of STP protocols (RSTP, MSTP or VSTP), and MVRP and ERP. Also, if any services depend on LLDP state (like PoE or VoIP device recognition), then these will also be affected. This issue affects: Junos OS: * 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 22.4R3,  * from 23.2 before 23.2R2. Junos OS Evolved: * from 21.4-EVO before 21.4R3-S5-EVO,  * from 22.1-EVO before 22.1R3-S4-EVO,  * from 22.2-EVO before 22.2R3-S2-EVO,  * from 22.3-EVO before 22.3R2-S2-EVO, 22.3R3-S1-EVO,  * from 22.4-EVO before 22.4R3-EVO,  * from 23.2-EVO before 23.2R2-EVO. This issue does not affect: * Junos OS versions prior to 21.4R1; * Junos OS Evolved versions prior to 21.4R1-EVO.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS: 21.4R3-S4, 22.1R3-S4, 22.2R3-S2, 22.3R2-S2, 22.3R3-S1, 22.4R3, 23.2R2, 23.4R1 and all subsequent releases. Junos OS Evolved: 21.4R3-S5-EVO, 22.1R3-S4-EVO, 22.2R3-S2-EVO, 22.3R2-S2-EVO, 22.3R3-S1-EVO, 22.4R3-EVO, 23.2R2-EVO, 23.4R1-EVO and all subsequent releases.

Workaround:

  • There are no available workarounds for this issue. ​​​​​​​ But if LLDP and its services are not required, customers can disable LLDP.

Categories

7.1
CVSS
Severity: High
CVSS 4.0 •
CVSS 3.1 •
EPSS 0.10%
Vendor Advisory juniper.net Vendor Advisory first.org
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS Evolved
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2024-21618?
CVE-2024-21618 has been scored as a high severity vulnerability.
How to fix CVE-2024-21618?
To fix CVE-2024-21618: The following software releases have been updated to resolve this specific issue: Junos OS: 21.4R3-S4, 22.1R3-S4, 22.2R3-S2, 22.3R2-S2, 22.3R3-S1, 22.4R3, 23.2R2, 23.4R1 and all subsequent releases. Junos OS Evolved: 21.4R3-S5-EVO, 22.1R3-S4-EVO, 22.2R3-S2-EVO, 22.3R2-S2-EVO, 22.3R3-S1-EVO, 22.4R3-EVO, 23.2R2-EVO, 23.4R1-EVO and all subsequent releases.
Is CVE-2024-21618 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-21618 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2024-21618?
CVE-2024-21618 affects Juniper Networks Junos OS, Juniper Networks Junos OS Evolved.
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