CVE-2023-36846Known exploitationPublic exploitNetwork attack vector

Unauthenticated file upload via J-Web user.php

Published Aug 17, 2023 · Updated Oct 21, 2025

Missing authentication in Junos OS SRX Series before 20.4R3-S8 allows remote attackers to upload files via J-Web. The user.php request accepts arbitrary file uploads without authentication, writing attacker-controlled content to part of the device filesystem. Internet or intranet reachability to J-Web is required; the demonstrated impact is limited filesystem integrity loss, which can enable chaining with other flaws rather than directly proving code execution.

CVSS severity5.3
Medium
EPSS probability94.82%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Missing authentication in Junos OS SRX Series before 20.4R3-S8 allows remote attackers to upload files via J-Web. The user.php request accepts arbitrary file uploads without authentication, writing attacker-controlled content to part of the device filesystem. Internet or intranet reachability to J-Web is required; the demonstrated impact is limited filesystem integrity loss, which can enable chaining with other flaws rather than directly proving code execution.

The record

CVE
CVE-2023-36846
Published
Aug 17, 2023
Updated
Oct 21, 2025
Vendor
Juniper Networks
Product
Junos OS
Classifications
CWE-306, CWE-434, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 17, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 13, 2023Exploitation reportedCISA Known Exploited Vulnerability listing
  3. Oct 21, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <20.4R3-S8
  2. Affected versionversion=21.1 <21.1*
  3. Affected versionversion=21.2 <21.2R3-S6
  4. Affected versionversion=21.3 <21.3R3-S5
  5. Affected versionversion=21.4 <21.4R3-S5
  6. Affected versionversion=22.1 <22.1R3-S3
  7. Affected versionversion=22.2 <22.2R3-S2
  8. Affected versionversion=22.3 <22.3R2-S2, 22.3R3
  9. Affected versionversion=22.4 <22.4R2-S1, 22.4R3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Juniper Networks · Junos OSversion=0 <20.4R3-S8; version=21.1 <21.1*; version=21.2 <21.2R3-S6; version=21.3 <21.3R3-S5; version=21.4 <21.4R3-S5; version=22.1 <22.1R3-S3; version=22.2 <22.2R3-S2; version=22.3 <22.3R2-S2, 22.3R3; version=22.4 <22.4R2-S1, 22.4R3

Published CVSS scores

5.3Juniper Networks CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-306CWE-306 Missing Authentication for Critical Function
CWE-434CWE-434 Unrestricted Upload of File with Dangerous Type
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Reported exploitation

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo