CVE-2018-0051: Juniper Junos

Medium severity, CVSS 5.9. EPSS: 1.6% chance of exploitation in the next 30 days.

A Denial of Service vulnerability in the SIP application layer gateway (ALG) component of Junos OS based platforms allows an attacker to crash MS-PIC, MS-MIC, MS-MPC, MS-DPC or SRX flow daemon (flowd) process. This issue affects Junos OS devices with NAT or stateful firewall configuration in combination with the SIP ALG enabled. SIP ALG is enabled by default on SRX Series devices except for SRX-HE devices. SRX-HE devices have SIP ALG disabled by default. The status of ALGs in SRX device can be obtained by executing the command: show security alg status Affected releases are Juniper Networks Junos OS: 12.1X46 versions prior to 12.1X46-D77; 12.3X48 versions prior to 12.3X48-D70; 15.1X49 versions prior to 15.1X49-D140; 15.1 versions prior to 15.1R4-S9, 15.1R7-S1; 15.1F6; 16.1 versions prior to 16.1R4-S9, 16.1R6-S1, 16.1R7; 16.2 versions prior to 16.2R2-S7, 16.2R3; 17.1 versions prior to 17.1R2-S7, 17.1R3; 17.2 versions prior to 17.2R1-S6, 17.2R2-S4, 17.2R3; 17.3 versions prior to 17.3R1-S5, 17.3R2-S2, 17.3R3; 17.4 versions prior to 17.4R2. No other Juniper Networks products or platforms are affected by this issue.

Affected products

• Juniper Junos: version 12.1x46 only; version 12.3x48 only; version 15.1x49 only; version 15.1 only; version 16.1 only; version 16.2 only; …

Published 2018-10-10. Last modified 2026-06-17.