CVE-2021-31370

MEDIUM

Juniper Junos OS QFX5000/EX4600 <21.1R2 DoS via High-Rate Multicast Traffic

Title source: llm
STIX 2.1

Description

An Incomplete List of Disallowed Inputs vulnerability in Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on QFX5000 Series and EX4600 Series allows an adjacent unauthenticated attacker which sends a high rate of specific multicast traffic to cause control traffic received from the network to be dropped. This will impact control protocols (including but not limited to routing-protocols) and lead to a Denial of Service (DoS). Continued receipt of this specific multicast traffic will create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS on QFX5000 and EX4600 Series: All versions prior to 17.3R3-S12; 17.4 versions prior to 17.4R3-S5; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R3-S9; 19.1 versions prior to 19.1R3-S6; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R1-S4, 19.4R3-S3; 20.1 versions prior to 20.1R2-S2, 20.1R3-S1; 20.2 versions prior to 20.2R3-S2; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2-S2, 20.4R3; 21.1 versions prior to 21.1R1-S1, 21.1R2.

References (1)

Core 1
Core References
Patch, Vendor Advisory x_refsource_confirm
https://kb.juniper.net/JSA11232

Scores

CVSS v3 6.5
EPSS 0.0041
EPSS Percentile 32.3%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Details

CWE
CWE-184
Status published
Products (2)
juniper/junos 17.3 (23 CPE variants)
juniper/junos 17.4 (27 CPE variants)
Published Oct 19, 2021
Tracked Since Feb 18, 2026