title: Junos OS and Junos OS Evolved: An l2cpd crash will occur when specific LLDP packets are received
description:
An Improper Validation of Specified Quantity in Input vulnerability in the Layer-2 control protocols daemon (l2cpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker who sends specific LLDP packets to cause a Denial of Service(DoS).
This issue occurs when specific LLDP packets are received and telemetry polling is being done on the device. 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:
Juniper Networks Junos OS
*  All versions prior to 20.4R3-S8;
*  21.1 version 21.1R1 and later versions;
*  21.2 versions prior to 21.2R3-S5;
*  21.3 versions prior to 21.3R3-S4;
*  21.4 versions prior to 21.4R3-S3;
*  22.1 versions prior to 22.1R3-S2;
*  22.2 versions prior to 22.2R3;
*  22.3 versions prior to 22.3R2-S2;
*  22.4 versions prior to 22.4R2;
Juniper Networks Junos OS Evolved
*  All versions prior to 20.4R3-S8-EVO;
*  21.1 version 21.1R1-EVO and later versions;
*  21.2 versions prior to 21.2R3-S5-EVO;
*  21.3 versions prior to 21.3R3-S4-EVO;
*  21.4 versions prior to 21.4R3-S3-EVO;
*  22.1 versions prior to 22.1R3-S2-EVO;
*  22.2 versions prior to 22.2R3-EVO;
*  22.3 versions prior to 22.3R2-S2-EVO;
*  22.4 versions prior to 22.4R1-S1-EVO;
problem types:  CWE-1284: Improper Validation of Specified Quantity in Input
affected:
{
defaultStatus: unaffected
product: Junos OS
vendor: Juniper Networks
versions:
lessThan: 20.4R3-S8, status: affected, version: 0, versionType: semver
lessThan: 21.1*, status: affected, version: 21.1R1, versionType: semver
lessThan: 21.2R3-S5, status: affected, version: 21.2, versionType: semver
lessThan: 21.3R3-S4, status: affected, version: 21.3, versionType: semver
lessThan: 21.4R3-S3, status: affected, version: 21.4, versionType: semver
lessThan: 22.1R3-S2, status: affected, version: 22.1, versionType: semver
lessThan: 22.2R3, status: affected, version: 22.2, versionType: semver
lessThan: 22.3R2-S2, 22.3R3, status: affected, version: 22.3, versionType: semver
lessThan: 22.4R2, status: affected, version: 22.4, versionType: semver
}
{
defaultStatus: unaffected
product: Junos OS Evolved
vendor: Juniper Networks
versions:
lessThan: 20.4R3-S8-EVO, status: affected, version: 0, versionType: semver
lessThan: 21.1*-EVO, status: affected, version: 21.1R1-EVO, versionType: semver
lessThan: 21.2R3-S5-EVO, status: affected, version: 21.2-EVO, versionType: semver
lessThan: 21.3R3-S4-EVO, status: affected, version: 21.3-EVO, versionType: semver
lessThan: 21.4R3-S3-EVO, status: affected, version: 21.4-EVO, versionType: semver
lessThan: 22.1R3-S2-EVO, status: affected, version: 22.1-EVO, versionType: semver
lessThan: 22.2R3-EVO, status: affected, version: 22.2-EVO, versionType: semver
lessThan: 22.3R2-S2-EVO, 22.3R3-EVO, status: affected, version: 22.3-EVO, versionType: semver
lessThan: 22.4R1-S1-EVO, 22.4R2-EVO, status: affected, version: 22.4-EVO, versionType: semver
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: ADJACENT_NETWORK
availabilityImpact: HIGH
baseScore: 6.5
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
version: 3.1
]
format: CVSS
scenarios: GENERAL
exploits: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
solutions: The following software releases have been updated to resolve this specific issue:
Junos OS: 20.4R3-S8, 21.2R3-S5, 21.3R3-S4, 21.4R3-S3, 22.1R3-S2, 22.2R3, 22.3R2-S2, 22.3R3, 22.4R2, 23.2R1, and all subsequent releases.
Junos OS Evolved: 20.4R3-S8-EVO, 21.2R3-S5-EVO, 21.3R3-S4-EVO, 21.4R3-S3-EVO, 22.1R3-S2-EVO, 22.2R3-EVO, 22.3R2-S2-EVO, 22.3R3-EVO, 22.4R1-S1-EVO, 22.4R2-EVO, 23.1R1-EVO, 23.1R2-EVO, 23.2R1-EVO
workarounds: If LLDP and its services are not required, customers can disable LLDP. Disabling telemetry polling also mitigates the issue.
There are no other known workarounds for this issue.