CVE-2018-0031

Junos OS: Receipt of specially crafted UDP packets over MPLS may bypass stateless IP firewall rules

Description

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.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 12.1X46-D76, 12.3X48-D66, 12.3X48-D70, 14.1X53-D47, 15.1F6-S10, 15.1R4-S9, 15.1R6-S6, 15.1R7, 15.1X49-D131, 15.1X49-D140, 15.1X53-D233, 15.1X53-D471, 15.1X53-D490, 15.1X53-D59, 15.1X53-D67, 16.1R3-S8, 16.1R4-S9, 16.1R5-S4, 16.1R6-S3, 16.1R7, 16.2R1-S6, 16.2R2-S5, 16.2R3, 17.1R1-S7, 17.1R2-S7, 17.1R3, 17.2R1-S6, 17.2R2-S4, 17.2R3, 17.2X75-D100, 17.3R1-S4, 17.3R2-S2, 17.3R3, 17.4R1-S3, 17.4R2, 18.1R2, 18.2R1, 18.2X75-D5, and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.

Category

5.3
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.19%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA10865 vendor advisory
http://www.securitytracker.com/id/1041326 vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2018-0031?
CVE-2018-0031 has been scored as a medium severity vulnerability.
How to fix CVE-2018-0031?
To fix CVE-2018-0031: The following software releases have been updated to resolve this specific issue: 12.1X46-D76, 12.3X48-D66, 12.3X48-D70, 14.1X53-D47, 15.1F6-S10, 15.1R4-S9, 15.1R6-S6, 15.1R7, 15.1X49-D131, 15.1X49-D140, 15.1X53-D233, 15.1X53-D471, 15.1X53-D490, 15.1X53-D59, 15.1X53-D67, 16.1R3-S8, 16.1R4-S9, 16.1R5-S4, 16.1R6-S3, 16.1R7, 16.2R1-S6, 16.2R2-S5, 16.2R3, 17.1R1-S7, 17.1R2-S7, 17.1R3, 17.2R1-S6, 17.2R2-S4, 17.2R3, 17.2X75-D100, 17.3R1-S4, 17.3R2-S2, 17.3R3, 17.4R1-S3, 17.4R2, 18.1R2, 18.2R1, 18.2X75-D5, and all subsequent releases.
Is CVE-2018-0031 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2018-0031 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2018-0031?
CVE-2018-0031 affects Juniper Networks Junos OS, Juniper Networks Junos OS, Juniper Networks Junos OS, Juniper Networks Junos OS, Juniper Networks Junos OS, Juniper Networks Junos OS, Juniper Networks Junos OS.
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