title: Junos OS: QFX5000 Series and EX4000 Series: Denial of Service (DoS) on a large scale VLAN due to PFE hogging
description:
An Allocation of Resources Without Limits or Throttling vulnerability in Juniper Networks Junos OS allows an unauthenticated, network-based attacker to cause Denial of Service (DoS).
On all Junos OS QFX5000 Series and EX4000 Series platforms, when a high number of VLANs are configured, a specific DHCP packet will cause PFE hogging which will lead to dropping of socket connections.
This issue affects:
Juniper Networks Junos OS on QFX5000 Series and EX4000 Series
*  21.1 versions prior to 21.1R3-S5;
*  21.2 versions prior to 21.2R3-S5;
*  21.3 versions prior to 21.3R3-S5;
*  21.4 versions prior to 21.4R3-S4;
*  22.1 versions prior to 22.1R3-S3;
*  22.2 versions prior to 22.2R3-S1;
*  22.3 versions prior to 22.3R2-S2, 22.3R3;
*  22.4 versions prior to 22.4R2.
This issue does not affect Juniper Networks Junos OS versions prior to 21.1R1
problem types: CWE-770 Allocation of Resources Without Limits or Throttling
affected:
{
defaultStatus: unaffected
platforms: [QFX5000 Series, EX4000 Series]
product: Junos OS
vendor: Juniper Networks
versions:
lessThan: 21.1R1, status: unaffected, version: 0, versionType: semver
lessThan: 21.1R3-S5, status: affected, version: 21.1, versionType: semver
lessThan: 21.2R3-S5, status: affected, version: 21.2, versionType: semver
lessThan: 21.3R3-S5, status: affected, version: 21.3, versionType: semver
lessThan: 21.4R3-S4, status: affected, version: 21.4, versionType: semver
lessThan: 22.1R3-S3, status: affected, version: 22.1, versionType: semver
lessThan: 22.2R3-S1, 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
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: HIGH
baseScore: 7.5
baseSeverity: HIGH
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/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 21.2R3-S5, 21.3R3-S5, 21.4R3-S4, 22.1R3-S3, 22.2R3-S1, 22.3R2-S2, 22.3R3, 22.4R2, 23.2R1, and all subsequent releases.
workarounds: There are no known workarounds for this issue.