CVE-2025-21601

HIGH

Juniper Junos < 21.4 - Denial of Service

Title source: rule
STIX 2.1

Description

An Improper Following of Specification by Caller vulnerability in web management (J-Web, Captive Portal, 802.1X, Juniper Secure Connect (JSC) of Juniper Networks Junos OS on SRX Series, EX Series, MX240, MX480, MX960, QFX5120 Series, allows an unauthenticated, network-based attacker, sending genuine traffic targeted to the device to cause the CPU to climb until the device becomes unresponsive. Continuous receipt of these packets will create a sustained Denial of Service (DoS) condition. This issue affects Junos OS:  * All versions before 21.4R3-S9, * from 22.2 before 22.2R3-S5, * from 22.4 before 22.4R3-S4, * from 23.2 before 23.2R2-S3, * from 23.4 before 23.4R2-S3, * from 24.2 before 24.2R1-S1, 24.2R2. An indicator of compromise is to review the CPU % of the httpd process in the CLI: e.g.   show system processes extensive | match httpd  PID nobody       52   0   20M    191M select   2   0:01   80.00% httpd{httpd} <<<<< the percentage of httpd usage if high may be an indicator

Scores

CVSS v3 7.5
EPSS 0.0047
EPSS Percentile 64.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-573
Status published
Products (5)
juniper/junos 21.4 r1 (15 CPE variants)
juniper/junos 22.2 (12 CPE variants)
juniper/junos 22.4 (11 CPE variants)
juniper/junos 23.2 (7 CPE variants)
juniper/junos 23.4 (5 CPE variants)
Published Apr 09, 2025
Tracked Since Feb 18, 2026