title: Junos OS: bbe-smgd process denial of service while processing VLAN authentication requests/rejects
description: A high rate of VLAN authentication attempts sent from an adjacent host on the local broadcast domain can trigger high memory utilization by the BBE subscriber management daemon (bbe-smgd), and lead to a denial of service condition. The issue was caused by attempting to process an unbounded number of pending VLAN authentication requests, leading to excessive memory allocation. This issue only affects devices configured for DHCPv4/v6 over AE auto-sensed VLANs, utilized in Broadband Edge (BBE) deployments. Other configurations are unaffected by this issue. Affected releases are Juniper Networks Junos OS: 15.1 versions prior to 15.1R6-S2, 15.1R7; 16.1 versions prior to 16.1R5-S1, 16.1R6; 16.2 versions prior to 16.2R2-S2, 16.2R3; 17.1 versions prior to 17.1R2-S5, 17.1R3; 17.2 versions prior to 17.2R2.
problem types: Denial of service
affected:
{
product: Junos OS
vendor: Juniper Networks
versions:
lessThan: 15.1R6-S2, 15.1R7, status: affected, version: 15.1, versionType: custom
lessThan: 16.1R5-S1, 16.1R6, status: affected, version: 16.1, versionType: custom
lessThan: 16.2R2-S2, 16.2R3, status: affected, version: 16.2, versionType: custom
lessThan: 17.1R2-S5, 17.1R3, status: affected, version: 17.1, versionType: custom
lessThan: 17.2R2, status: affected, version: 17.2, versionType: custom
}
metrics:
cvssV3_0: [
attackComplexity: LOW
attackVector: ADJACENT_NETWORK
availabilityImpact: HIGH
baseScore: 6.5
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.0/AV:A/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 this specific issue: 15.1R6-S2, 15.1R7, 16.1R5-S1, 16.1R6, 16.2R2-S2, 16.2R3, 17.1R2-S5*, 17.1R3*, 17.2R2, 17.3R1, 17.4R1, and all subsequent releases.
*pending release
workarounds: Since this issue is specific to auto-sense or dynamic VLANs, utilizing a static VLAN model will mitigate this issue.