CVE-2019-0031
Junos OS: jdhcpd daemon memory consumption Denial of Service when receiving specific IPv6 DHCP packets.
- 7.4HighCVSS base score
- 1.7%Exploitation in 30 daysEPSS · top 22% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By juniper
- 6 months later
· 6 months later
Published
- 5 years later
· 5 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| juniperCNA (assigner) | 3.0 | High7.4 | CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 1.7% · top 22% of all CVEs (11 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.4.
Affected products
- affected 17.4 – < 17.4R2
- affected 18.1 – < 18.1R2
What to do
Solution: The following software releases have been updated to resolve this specific issue: 17.4R2, 18.1R2, 18.2R1, and all subsequent releases.
Workaround: Customers may discontinue processing or serving DHCPv6 address assignments until such time that fixes can be taken. This workaround is helpful for large IPv4 environments with fewer or considered less important IPv6 clients.
Exploitation: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
References
References2
- https://kb.juniper.net/JSA10920 (opens in a new tab)x_refsource_CONFIRMx_transferred
- 107874 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2019-0838 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2019-0031)Record last updated .