CVE-2021-31376

HIGH

Juniper Junos OS 18.4R3-S7-18.4R3-S8 on ACX Series - Denial of Service via DHCPv6 Packet Processing

Title source: llm
STIX 2.1

Description

An Improper Input Validation vulnerability in Packet Forwarding Engine manager (FXPC) process of Juniper Networks Junos OS allows an attacker to cause a Denial of Service (DoS) by sending specific DHCPv6 packets to the device and crashing the FXPC service. Continued receipt and processing of this specific packet will create a sustained Denial of Service (DoS) condition. This issue affects only the following platforms in ACX Series: ACX500, ACX1000, ACX1100, ACX2100, ACX2200, ACX4000, ACX5048, ACX5096 devices. Other ACX platforms are not affected from this issue. This issue affects Juniper Networks Junos OS on ACX500, ACX1000, ACX1100, ACX2100, ACX2200, ACX4000, ACX5048, ACX5096: 18.4 version 18.4R3-S7 and later versions prior to 18.4R3-S8. This issue does not affect: Juniper Networks Junos OS 18.4 versions prior to 18.4R3-S7 on ACX500, ACX1000, ACX1100, ACX2100, ACX2200, ACX4000, ACX5048, ACX5096.

References (1)

Core 1
Core References
Vendor Advisory x_refsource_confirm
https://kb.juniper.net/JSA11241

Scores

CVSS v3 7.5
EPSS 0.0039
EPSS Percentile 60.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Details

CWE
CWE-20
Status published
Products (1)
juniper/junos 18.4 r3-s7
Published Oct 19, 2021
Tracked Since Feb 18, 2026