CVE-2025-21601

Junos OS: SRX and EX Series, MX240, MX480, MX960, QFX5120 Series: When web management is enabled for specific services an attacker may cause a CPU spike by sending genuine packets to the device

Published Apr 9, 2025 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
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

Remediation

Vendor Solution

The following software releases have been updated to resolve this specific issue: Junos OS: 21.4R3-S9, 22.2R3-S5, 22.4R3-S4, 23.2R2-S3, 23.4R2-S3, 24.2R1-S1, 24.2R2, 24.4R1, and all subsequent releases.


Vendor Workaround

There are no known workarounds for this issue. To reduce the risk of exploitation use authentication when using web management services.

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
EUVD EUVD EUVD-2025-10526 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
References
History
Type Values Removed Values Added
First Time appeared Juniper
Juniper junos
CPEs cpe:2.3:o:juniper:junos:*:*:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r1-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r2-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r2-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r3-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r3-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r3-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r3-s4:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r3-s5:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r3-s6:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r3-s7:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r3-s8:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:21.4:r3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r1-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r2-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r2-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r3-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r3-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r3-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r3-s4:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.2:r3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r1-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r2-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r2-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r3-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r3-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r3-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:22.4:r3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.2:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.2:r1-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.2:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.2:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.2:r2-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.2:r2-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.2:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.4:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.4:r1-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.4:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.4:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.4:r2-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.4:r2-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:23.4:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:24.2:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:24.2:r1:*:*:*:*:*:*
Vendors & Products Juniper
Juniper junos
Type Values Removed Values Added
Weaknesses CWE-573
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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
Title Junos OS: SRX and EX Series, MX240, MX480, MX960, QFX5120 Series: When web management is enabled for specific services an attacker may cause a CPU spike by sending genuine packets to the device
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/V:C/RE:M/U:Amber'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
juniper
Published
Updated
Apr 15, 2025, 8:30 PM
Reserved
Dec 26, 2024, 2:47 PM
Status
Analyzed
Published
Apr 9, 2025, 8:15 PM
Modified
Jun 17, 2026, 8:43 AM