Junos OS and Junos OS Evolved: Unix socket used to control the jdhcpd process is world-writable

Summary

An Incorrect Permission Assignment for Critical Resource vulnerability in the Juniper DHCP daemon (jdhcpd) of Juniper Networks Junos OS and Junos OS Evolved allows a local, low-privileged user to write to the Unix socket used to manage the jdhcpd process, resulting in complete control over the resource. This vulnerability allows any low-privileged user logged into the system to connect to the Unix socket and issue commands to manage the DHCP service, in essence, taking administrative control of the local DHCP server or DHCP relay. This issue affects: Junos OS: • all versions before 21.2R3-S10, • all versions of 22.2, • from 21.4 before 21.4R3-S12, • from 22.4 before 22.4R3-S8, • from 23.2 before 23.2R2-S5, • from 23.4 before 23.4R2-S6, • from 24.2 before 24.2R2-S2, • from 24.4 before 24.4R2, • from 25.2 before 25.2R1-S1, 25.2R2; Junos OS Evolved: • all versions before 22.4R3-S8-EVO, • from 23.2 before 23.2R2-S5-EVO, • from 23.4 before 23.4R2-S6-EVO, • from 24.2 before 24.2R2-S2-EVO, • from 24.4 before 24.4R2-EVO, • from 25.2 before 25.2R1-S1-EVO, 25.2R2-EVO.

Timeline

1. Jan 15, 2026, 8:14 PM UTCCVE published
2. Jan 15, 2026, 9:08 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Jan 15, 2026, 9:08 PM UTCRecord last updated

Affected versions

• Juniper Networks Junos OS

  fixed in 21.2R3-S10; From 21.4 · fixed in 21.4R3-S12; From 22.2; From 22.4 · fixed in 22.4R3-S8; From 23.2 · fixed in 23.2R2-S5; From 23.4 · fixed in 23.4R2-S6; From 24.2 · fixed in 24.2R2-S2; From 24.4 · fixed in 24.4R2

• Juniper Networks Junos OS Evolved

  fixed in 22.4R3-S8-EVO; From 23.2 · fixed in 23.2R2-S5-EVO; From 23.4 · fixed in 23.4R2-S6-EVO; From 24.2 · fixed in 24.2R2-S2-EVO; From 24.4 · fixed in 24.4R2-EVO

References 2