CVE-2025-21601

High

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

SeverityHigh
CVSS7.5
Exploit probability—
ProductJuniper Junos
PublishedApr 9, 2025
First seenApr 9, 2025
Weakness typeCWE-573CWE-573

How to fix

Affected products

ProductAffected versionsFixed in
juniper junosv ≤ 21.4, 21.4, 22.2, 22.4, 23.2, 23.4, 24.2—

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CVE-2025-21601 · Juniper Junos · Dark Radar