CVE-2023-44191: Junos OS: QFX5000 Series and EX4000 Series: Denial of Service (DoS) on a large scale VLAN due to PFE hogging

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-10-13 · updated 2026-06-17
Weakness: CWE-770

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

Affected products

Juniper Junos OS: 21.1, 21.1-r1, 21.1-r1-s1, 21.1-r2, 21.1-r2-s1, 21.1-r2-s2 (+62)

References

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