title: Junos OS: MX Series: The bbe-smgd process crashes if an unsupported configuration exists and a PPPoE client sends a specific message
description: An Unchecked Error Condition vulnerability in the subscriber management daemon (smgd) of Juniper Networks Junos OS allows an unauthenticated adjacent attacker to cause a crash of and thereby a Denial of Service (DoS). In a subscriber management / broadband edge environment if a single session group configuration contains dual-stack and a pp0 interface, smgd will crash and restart every time a PPPoE client sends a specific message. This issue affects Juniper Networks Junos OS on MX Series: 16.1 version 16.1R1 and later versions prior to 18.4R3-S10; 19.1 versions prior to 19.1R2-S3, 19.1R3-S7; 19.2 versions prior to 19.2R1-S8, 19.2R3-S4; 19.3 versions prior to 19.3R3-S4; 19.4 versions prior to 19.4R3-S5; 20.1 versions prior to 20.1R3-S3; 20.2 versions prior to 20.2R3-S3; 20.3 versions prior to 20.3R3-S2; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2. This issue does not affect Juniper Networks Junos OS versions prior to 16.1R1.
problem types: CWE-391 Unchecked Error Condition
affected:
{
platforms: MX Series
product: Junos OS
vendor: Juniper Networks
versions:
lessThan: 18.4R3-S10, status: affected, version: unspecified, versionType: custom
lessThan: 16.1R1, status: unaffected, version: unspecified, versionType: custom
lessThan: 16.1*, status: affected, version: 16.1R1, versionType: custom
lessThan: 19.1R2-S3, 19.1R3-S7, status: affected, version: 19.1, versionType: custom
lessThan: 19.2R1-S8, 19.2R3-S4, status: affected, version: 19.2, versionType: custom
lessThan: 19.3R3-S4, status: affected, version: 19.3, versionType: custom
lessThan: 19.4R3-S5, status: affected, version: 19.4, versionType: custom
lessThan: 20.1R3-S3, status: affected, version: 20.1, versionType: custom
lessThan: 20.2R3-S3, status: affected, version: 20.2, versionType: custom
lessThan: 20.3R3-S2, status: affected, version: 20.3, versionType: custom
lessThan: 20.4R3, status: affected, version: 20.4, versionType: custom
lessThan: 21.1R3, status: affected, version: 21.1, versionType: custom
lessThan: 21.2R2, status: affected, version: 21.2, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: ADJACENT_NETWORK
availabilityImpact: HIGH
baseScore: 6.5
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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: 18.4R3-S10, 19.1R2-S3, 19.1R3-S7, 19.2R1-S8, 19.2R3-S4, 19.3R3-S4, 19.4R3-S5, 20.1R3-S3, 20.2R3-S3, 20.3R3-S2, 20.4R3, 21.1R3, 21.2R2, 21.3R1, and all subsequent releases.
workarounds: Remove the pp0 interface from a DHCPv6 dual-stack group and move to its own group with no dual-stack enabled.
user@device# show system services dhcp-local-server dhcpv6
...
group <group-name1> {
overrides {
...
dual-stack <dual-stack-group-name>;
}
...
interface pp0.0; <<<<< delete and add to new group
...
}
group <group-name2> { <<<<< new group for PP0 interfaces to be handled separately.
...
interface pp0.0; <<<<<
...
}
