vulnerability

Juniper Junos OS: 2021-04 Security Bulletin: Junos OS: Receipt of a crafted DHCP packet will cause the jdhcpd DHCP service to core. (JSA11158) (CVE-2021-0267)

Severity
3
CVSS
(AV:A/AC:L/Au:N/C:N/I:N/A:P)
Published
Apr 22, 2021
Added
Apr 27, 2021
Modified
Aug 11, 2025

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.

Solution

juniper-junos-os-upgrade-latest
Title
NEW

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