CVE-2026-33782 PUBLISHED

Junos OS: MX Series: In specific DHCPv6 scenarios jdhcpd memory increases continuously with subscriber logouts

Assigner: juniper
Reserved: 23.03.2026 Published: 09.04.2026 Updated: 09.04.2026

A Missing Release of Memory after Effective Lifetime vulnerability in the DHCP daemon (jdhcpd) of Juniper Networks Junos OS on MX Series, allows an adjacent, unauthenticated attacker to cause a memory leak, that will eventually cause a complete Denial-of-Service (DoS).

In a DHCPv6 over PPPoE, or DHCPv6 over VLAN with Active lease query or Bulk lease query scenario, every subscriber logout will leak a small amount of memory. When all available memory has been exhausted, jdhcpd will crash and restart which causes a complete service impact until the process has recovered.

The memory usage of jdhcpd can be monitored with:

user@host> show system processes extensive | match jdhcpd

This issue affects Junos OS:

  • all versions before 22.4R3-S1,
  • 23.2 versions before 23.2R2,
  • 23.4 versions before 23.4R2.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/RE:M
CVSS Score: 8.7

Product Status

Vendor Juniper Networks
Product Junos OS
Versions Default: unaffected
  • affected from 0 to 22.4R3-S1 (excl.)
  • affected from 23.2 to 23.2R2 (excl.)
  • affected from 23.4 to 23.4R2 (excl.)

Exploits

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

Workarounds

There are no known workarounds for this issue.

Solutions

The following software releases have been updated to resolve this specific issue: 22.4R3-S1, 23.2R2, 23.4R2, 24.2R1, and all subsequent releases.

References

Problem Types

  • CWE-401 Missing Release of Memory after Effective Lifetime CWE