title: Junos OS: Denial of Service vulnerability in MS-PIC, MS-MIC, MS-MPC, MS-DPC and SRX flow daemon (flowd) related to SIP ALG
description: 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.
problem types: Denial of Service
affected:
{
platforms: SRX Series
product: Junos OS
vendor: Juniper Networks
versions:
lessThan: 12.1X46-D77, status: affected, version: 12.1X46, versionType: custom
lessThan: 12.3X48-D70, status: affected, version: 12.3X48, versionType: custom
lessThan: 15.1X49-D140, status: affected, version: 15.1X49, versionType: custom
}
{
product: Junos OS
vendor: Juniper Networks
versions:
status: affected, version: 15.1F6
lessThan: 15.1R4-S9, 15.1R7-S1, status: affected, version: 15.1, versionType: custom
lessThan: 16.1R4-S9, 16.1R6-S1, 16.1R7, status: affected, version: 16.1, versionType: custom
lessThan: 16.2R2-S7, 16.2R3, status: affected, version: 16.2, versionType: custom
lessThan: 17.1R2-S7, 17.1R3, status: affected, version: 17.1, versionType: custom
lessThan: 17.2R1-S6, 17.2R2-S4, 17.2R3, status: affected, version: 17.2, versionType: custom
lessThan: 17.3R1-S5, 17.3R2-S2, 17.3R3, status: affected, version: 17.3, versionType: custom
lessThan: 17.4R2, status: affected, version: 17.4, versionType: custom
}
metrics:
cvssV3_0: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: HIGH
baseScore: 7.5
baseSeverity: HIGH
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
version: 3.0
]
exploits: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
solutions: The following software releases have been updated to resolve these specific issues: 12.1X46-D77, 12.3X48-D70, 12.3X48-D75, 14.1X53-D47, 15.1R4-S9, 15.1R7-S1, 15.1X49-D140, 15.1X53-D471, 15.1X53-D490, 15.1X53-D59, 15.1X53-D67, 16.1R4-S9, 16.1R6-S1, 16.1R7, 16.2R2-S7, 16.2R3, 17.1R2-S7, 17.1R3, 17.2R1-S6, 17.2R2-S4, 17.2R3, 17.3R1-S5, 17.3R2-S2, 17.3R3, 17.4R2, 18.1R1, 18.1X75-D10, 18.2R1, 18.2X75-D5, and all subsequent releases.
This fix has also been proactively committed into other releases that might not support SIP ALG configuration.
workarounds:  Disable the use of the SIP ALG feature if it is not needed.