title: Junos OS: Kernel panic upon receipt of specific TCPv6 packet on management interface
description: A vulnerability in the forwarding of transit TCPv6 packets received on the Ethernet management interface of Juniper Networks Junos OS allows an attacker to trigger a kernel panic, leading to a Denial of Service (DoS). Continued receipt and processing of these transit packets will create a sustained Denial of Service (DoS) condition. This issue only occurs when TCPv6 packets are routed through the management interface. Other transit traffic, and traffic destined to the management interface, are unaffected by this vulnerability. This issue was introduced as part of a TCP Parallelization feature added in Junos OS 17.2, and affects systems with concurrent network stack enabled. This feature is enabled by default, but can be disabled (see WORKAROUND section below). This issue affects Juniper Networks Junos OS: 17.2 versions prior to 17.2R3-S4; 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S5; 18.3 versions prior to 18.3R2-S4, 18.3R3-S3; 18.4 versions prior to 18.4R2-S5, 18.4R3-S4; 19.1 versions prior to 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2. This issue does not affect Juniper Networks Junos OS versions prior to 17.2R1.
problem types: CWE-362 Race Condition (Concurrent Execution using Shared Resource with Improper Synchronization)
affected:
{
product: Junos OS
vendor: Juniper Networks
versions:
changes: [at: 17.2R3-S4, status: unaffected], lessThan: 17.2R1, status: unaffected, version: 17.2, versionType: custom
lessThan: 17.3R3-S9, status: affected, version: 17.3, versionType: custom
lessThan: 17.4R2-S11, 17.4R3-S2, status: affected, version: 17.4, versionType: custom
lessThan: 18.1R3-S11, status: affected, version: 18.1, versionType: custom
lessThan: 18.2R3-S5, status: affected, version: 18.2, versionType: custom
lessThan: 18.3R2-S4, 18.3R3-S3, status: affected, version: 18.3, versionType: custom
lessThan: 18.4R2-S5, 18.4R3-S4, status: affected, version: 18.4, versionType: custom
lessThan: 19.1R2-S2, 19.1R3, status: affected, version: 19.1, versionType: custom
lessThan: 19.2R1-S5, 19.2R2, status: affected, version: 19.2, versionType: custom
lessThan: 19.3R2-S4, 19.3R3, status: affected, version: 19.3, versionType: custom
lessThan: 19.4R1-S3, 19.4R2, status: affected, version: 19.4, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: HIGH
baseScore: 5.9
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:H/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: Junos OS 17.2R3-S4, 17.3R3-S9, 17.4R2-S11, 17.4R3-S2, 18.1R3-S11, 18.2R3-S5, 18.3R2-S4, 18.3R3-S3, 18.4R2-S5, 18.4R3-S4, 19.1R2-S2, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2, 20.1R1, and all subsequent releases.
workarounds: Disable TCP Parallelization:
set system kernel-smp-features disable-concurrent-network-stack