Vulnerability Database

324,311

Total vulnerabilities in the database

CVE-2025-21591

A Buffer Access with Incorrect Length Value vulnerability in the jdhcpd daemon of Juniper Networks Junos OS, when DHCP snooping is enabled, allows an unauthenticated, adjacent, attacker to send a DHCP packet with a malformed DHCP option to cause jdhcp to crash creating a Denial of Service (DoS) condition.

Continuous receipt of these DHCP packets using the malformed DHCP Option will create a sustained Denial of Service (DoS) condition.

This issue affects Junos OS:

  • from 23.1 before 23.2R2-S3,
  • from 23.4 before 23.4R2-S3,
  • from 24.2 before 24.2R2.

This issue isn't applicable to any versions of Junos OS before 23.1R1.

This issue doesn't affect vSRX Series which doesn't support DHCP Snooping.

This issue doesn't affect Junos OS Evolved.

There are no indicators of compromise for this issue.

  • Published: Apr 9, 2025
  • Updated: Nov 16, 2025
  • CVE: CVE-2025-21591
  • Severity: High
  • Exploit:

CVSS v3:

  • Severity: High
  • Score: 7.4
  • AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

CWEs:

Software From Fixed in
juniper / junos 23.1-r1 23.1-r1.x
juniper / junos 23.2 23.2.x
juniper / junos 23.2-r1 23.2-r1.x
juniper / junos 23.2-r1-s1 23.2-r1-s1.x
juniper / junos 23.2-r1-s2 23.2-r1-s2.x
juniper / junos 23.2-r2 23.2-r2.x
juniper / junos 23.2-r2-s1 23.2-r2-s1.x
juniper / junos 23.2-r2-s2 23.2-r2-s2.x
juniper / junos 23.4 23.4.x
juniper / junos 23.4-r1 23.4-r1.x
juniper / junos 23.4-r1-s1 23.4-r1-s1.x
juniper / junos 23.4-r1-s2 23.4-r1-s2.x
juniper / junos 23.4-r2 23.4-r2.x
juniper / junos 23.4-r2-s1 23.4-r2-s1.x
juniper / junos 23.4-r2-s2 23.4-r2-s2.x
juniper / junos 24.2 24.2.x
juniper / junos 24.2-r1 24.2-r1.x
juniper / junos 24.2-r1-s1 24.2-r1-s1.x
juniper / junos 24.2-r1-s2 24.2-r1-s2.x