CVE-2025-59960

Summary

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Juniper DHCP service (jdhcpd) of Juniper Networks Junos OS and Junos OS Evolved allows a DHCP client in one subnet to exhaust the address pools of other subnets, leading to a Denial of Service (DoS) on the downstream DHCP server.

By default, the DHCP relay agent inserts its own Option 82 information when forwarding client requests, optionally replacing any Option 82 information provided by the client. When a specific DHCP DISCOVER is received in 'forward-only' mode with Option 82, the device should drop the message unless 'trust-option82' is configured. Instead, the DHCP relay forwards these packets to the DHCP server unmodified, which uses up addresses in the DHCP server's address pool, ultimately leading to address pool exhaustion.

This issue affects Junos OS: 

  • all versions before 21.2R3-S10,
  • from 21.4 before 21.4R3-S12,
  • all versions of 22.2,
  • 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 21.4R3-S12-EVO, 
  • all versions of 22.2-EVO,
  • from 22.4 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.

Affected Software

VendorProductVersion RangeStatus
Juniper NetworksJunos OS0 < 21.2R3-S10affected
Juniper NetworksJunos OS21.4 < 21.4R3-S12affected
Juniper NetworksJunos OS22.2 < 22.2*affected
Juniper NetworksJunos OS22.4 < 22.4R3-S8affected
Juniper NetworksJunos OS23.2 < 23.2R2-S5affected
Juniper NetworksJunos OS23.4 < 23.4R2-S6affected
Juniper NetworksJunos OS24.2 < 24.2R2-S2affected
Juniper NetworksJunos OS24.4 < 24.4R2affected
Juniper NetworksJunos OS25.2 < 25.2R1-S1, 25.2R2affected
Juniper NetworksJunos OS Evolved0 < 21.4R3-S12-EVOaffected
Juniper NetworksJunos OS Evolved22.2 < 22.2*affected
Juniper NetworksJunos OS Evolved22.4 < 22.4R3-S8-EVOaffected
Juniper NetworksJunos OS Evolved23.2 < 23.2R2-S5-EVOaffected
Juniper NetworksJunos OS Evolved23.4 < 23.4R2-S6-EVOaffected
Juniper NetworksJunos OS Evolved24.2 < 24.2R2-S2-EVOaffected
Juniper NetworksJunos OS Evolved24.4 < 24.4R2-EVOaffected
Juniper NetworksJunos OS Evolved25.2 < 25.2R1-S1-EVO, 25.2R2-EVOaffected

Weaknesses

  • CWE-754: CWE-754 Improper Check for Unusual or Exceptional Conditions

Workarounds

There are no known workarounds for this issue.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References