title: Junos OS: MX Series: Receipt of specific packets can cause services card to restart when DNS filtering is configured.
description: When DNS filtering is enabled on Juniper Networks Junos MX Series with one of the following cards MS-PIC, MS-MIC or MS-MPC, an incoming stream of packets processed by the Multiservices PIC Management Daemon (mspmand) process, responsible for managing "URL Filtering service", may crash, causing the Services PIC to restart. While the Services PIC is restarting, all PIC services including DNS filtering service (DNS sink holing) will be bypassed until the Services PIC completes its boot process. This vulnerability might allow an attacker to cause an extended Denial of Service (DoS) attack against the device and to cause clients to be vulnerable to DNS based attacks by malicious DNS servers when they send DNS requests through the device. As a result, devices which were once protected by the DNS Filtering service are no longer protected and at risk of exploitation. This issue affects Juniper Networks Junos OS: 17.3 versions prior to 17.3R3-S8; 18.3 versions prior to 18.3R3-S1; 18.4 versions prior to 18.4R3; 19.1 versions prior to 19.1R3; 19.2 versions prior to 19.2R2; 19.3 versions prior to 19.3R3. This issue does not affect Juniper Networks Junos OS 17.4, 18.1, and 18.2.
problem types: Denial of Service
affected:
{
platforms: MX Series
product: Junos OS
vendor: Juniper Networks
versions:
lessThan: 17.3R3-S8, status: affected, version: 17.3, versionType: custom
lessThan: 18.3R3-S1, status: affected, version: 18.3, versionType: custom
lessThan: 18.4R3, status: affected, version: 18.4, versionType: custom
lessThan: 19.1R3, status: affected, version: 19.1, versionType: custom
lessThan: 19.2R2, status: affected, version: 19.2, versionType: custom
lessThan: 19.3R3, status: affected, version: 19.3, versionType: custom
}
{
product: Junos OS
vendor: Juniper Networks
versions:
status: unaffected, version: 17.4
status: unaffected, version: 18.1
status: unaffected, version: 18.2
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 8.3
baseSeverity: HIGH
confidentialityImpact: LOW
integrityImpact: LOW
privilegesRequired: NONE
scope: CHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
version: 3.1
]
exploits: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
solutions: The following software releases have been updated to resolve this specific issue: Junos OS 17.3R3-S8, 18.3R3-S1, 18.4R3, 19.1R3, 19.2R2, 19.3R3, 19.4R1 and all subsequent releases.
workarounds: There are no viable workarounds for this issue.