What is CVE-2018-0031?

CVE-2018-0031 is a medium-severity vulnerability in Juniper Ex2300, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2018-07-11.

How severe is CVE-2018-0031?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Resource exhaustion in Juniper Ex2300

CVE-2018-0031

Receipt of specially crafted UDP/IP packets over MPLS may be able to bypass a stateless firewall filter. The crafted UDP packets must be encapsulated and meet a very specific packet format to be classified in a way that bypasses IP firewall filter rules. The packets themselves do not cause a service interruption (e.g. RPD crash), but receipt of a high rate of UDP packets may be able to contribute to a denial of service attack. This issue only affects processing of transit UDP/IP packets over MPLS, received on an interface with MPLS enabled. TCP packet processing and non-MPLS encapsulated UDP packet processing are unaffected by this issue. Affected releases are Juniper Networks Junos OS: 12.1X46 versions prior to 12.1X46-D76; 12.3 versions prior to 12.3R12-S10; 12.3X48 versions prior to 12.3X48-D66, 12.3X48-D70; 14.1X53 versions prior to 14.1X53-D47; 15.1 versions prior to 15.1F6-S10, 15.1R4-S9, 15.1R6-S6, 15.1R7; 15.1X49 versions prior to 15.1X49-D131, 15.1X49-D140; 15.1X53 versions prior to 15.1X53-D59 on EX2300/EX3400; 15.1X53 versions prior to 15.1X53-D67 on QFX10K; 15.1X53 versions prior to 15.1X53-D233 on QFX5200/QFX5110; 15.1X53 versions prior to 15.1X53-D471, 15.1X53-D490 on NFX; 16.1 versions prior to 16.1R3-S8, 16.1R4-S9, 16.1R5-S4, 16.1R6-S3, 16.1R7; 16.2 versions prior to 16.2R1-S6, 16.2R2-S5, 16.2R3; 17.1 versions prior to 17.1R1-S7, 17.1R2-S7, 17.1R3; 17.2 versions prior to 17.2R1-S6, 17.2R2-S4, 17.2R3; 17.2X75 versions prior to 17.2X75-D100; 17.3 versions prior to 17.3R1-S4, 17.3R2-S2, 17.3R3; 17.4 versions prior to 17.4R1-S3, 17.4R2; 18.1 versions prior to 18.1R2; 18.2X75 versions prior to 18.2X75-D5.

Vulnerability class: DoS (Denial of Service)

Published 2018-07-11 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.012 (68.1th percentile), scored 2026-10-20.

Low probability of exploitation in the next 30 days, but still tracked. 68th percentile — 68.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: 0.000

Affected products

Juniper Ex2300
Juniper Ex3400
Juniper Junos — versions 12.1x46, 12.3, 12.3x48
Juniper Nfx250
Juniper Qfx10000
Juniper Qfx5110
Juniper Qfx5200
Juniper Networks Junos OS — versions 18.2X75, 18.1, 16.1

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption

References

kb.juniper.net/JSA10865 (Vendor Advisory)
www.securitytracker.com/id/1041326 (VDB Entry, Third Party Advisory, vdb-entry)

Frequently asked questions

What is CVE-2018-0031?: CVE-2018-0031 is a medium-severity vulnerability in Juniper Ex2300, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2018-07-11.
How severe is CVE-2018-0031?: Medium severity. CVSS v3 base score is 5.3 out of 10.