CVE-2021-0267

MediumCVSS 6.5/10Last modified Jun 17, 2026

Description

An Improper Input Validation vulnerability in the active-lease query portion in JDHCPD's DHCP Relay Agent of Juniper Networks Junos OS allows an attacker to cause a Denial of Service (DoS) by sending a crafted DHCP packet to the device thereby crashing the jdhcpd DHCP service. This is typically configured for Broadband Subscriber Sessions. Continued receipt and processing of this crafted packet will create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS: 19.4 versions prior to 19.4R3-S1; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R3; 20.3 versions prior to 20.3R2. This issue does not affect Junos OS Evolved.

Metrics

CVSS 3.1 6.5/10CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

CWE-20

Affected software

VendorProductVersions
Juniper NetworksJunos OS>= 19.4, < 19.4R3-S1; >= 20.1, < 20.1R2-S1, 20.1R3; >= 20.2, < 20.2R3; >= 20.3, < 20.3R2

References

Timeline

Published
Apr 22, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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