CVE-2026-102057: CWE-121 Stack-based Buffer Overflow in Juniper Networks Junos OS

This vulnerability is a stack-based buffer overflow (CWE-121) in the jdhcpd process of Juniper Networks Junos OS. An unauthenticated attacker on an adjacent network can exploit this by sending a malicious DHCP client response, causing a denial of service condition. The flaw specifically impacts DHCP client functionality and related services such as DHCP relay and zero-touch provisioning. The vulnerability has a CVSS 3.1 base score of 7.5, indicating high severity with network attack vector, low attack complexity, no privileges or user interaction required, and causing availability impact only. Multiple Junos OS versions are affected, with fixed versions starting from 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, and 26.2R1-S2 respectively.

Exploitation results in denial of service by crashing or interrupting the DHCP client process on Junos OS devices. This disruption affects DHCP client operations and can interrupt DHCP relay and zero-touch provisioning services, potentially impacting network connectivity and automated device provisioning.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. The affected versions indicate that fixed releases exist starting from 23.2R2-S7.7 and similar versions for other branches. Users should verify with Juniper Networks for official patches or updates addressing this vulnerability. Until patched, network administrators should consider isolating DHCP client traffic from untrusted adjacent networks to reduce exposure.