Junos OS: jdhcpd daemon memory consumption Denial of Service when receiving specific IPv6 DHCP packets.

published 2019-04-10 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-0838

cvss: 7.4; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.7%; EPSS 1.7% chance of exploitation in 30 days, percentile 77%
public exploits: 0; none known

Specific IPv6 DHCP packets received by the jdhcpd daemon will cause a memory resource consumption issue to occur on a Junos OS device using the jdhcpd daemon configured to respond to IPv6 requests. Once started, memory consumption will eventually impact any IPv4 or IPv6 request serviced by the jdhcpd daemon, thus creating a Denial of Service (DoS) condition to clients requesting and not receiving IP addresses. Additionally, some clients which were previously holding IPv6 addresses will not have their IPv6 Identity Association (IA) address and network tables agreed upon by the jdhcpd daemon after the failover event occurs, which leads to more than one interface, and multiple IP addresses, being denied on the client. Affected releases are Juniper Networks Junos OS: 17.4 versions prior to 17.4R2; 18.1 versions prior to 18.1R2.

Patch / fix

fixed in 1

Juniper Networks Junos OS 17.4R2, 18.1R2

Exploit prediction

1.71% chance of exploitation in the next 30 days, higher than 77% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.0	7.4	CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

Juniper Networks Junos OS

Classification

Weakness

CWE-400 Uncontrolled Resource Consumption
CWE-770 Allocation of Resources Without Limits or Throttling

References

kb.juniper.net /JSA10920
vendor-advisory
securityfocus.com /bid/107874
vdb-entry, third-party-advisory

Sources

CVE List CVE-2019-0031
NVD CVE-2019-0031

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Summary