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Medium · 5.3 Known exploited Public exploit CVE-2023-36846 EUVD-2023-40766GHSA-rrhw-mwxf-m9mp

Junos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary files

Published Aug 17, 2023 · Updated Oct 21, 2025 · Assigned by juniper

Description

A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause limited impact to the file system integrity.

With a specific request to user.php that doesn't require authentication an attacker is able to upload arbitrary files via J-Web, leading to a loss of

integrity

for a certain 

part of the file system, which may allow chaining to other vulnerabilities.

This issue affects Juniper Networks Junos OS on SRX Series:

* All versions prior to 20.4R3-S8;
* 21.1 versions 21.1R1 and later;
* 21.2 versions prior to 21.2R3-S6;
* 21.3 versions

prior to

21.3R3-S5;
* 21.4 versions

prior to

21.4R3-S5;
* 22.1 versions

prior to

22.1R3-S3;
* 22.2 versions

prior to

22.2R3-S2;
* 22.3 versions

prior to

22.3R2-S2, 22.3R3;
* 22.4 versions

prior to

22.4R2-S1, 22.4R3.

Affected products

VendorProductAffectedFixed
Juniper Networks Junos OS < 20.4R3-S8, 21.1 – < 21.1*, 21.2 – < 21.2R3-S6, 21.3 – < 21.3R3-S5, 21.4 – < 21.4R3-S5, 22.1 – < 22.1R3-S3, 22.2 – < 22.2R3-S2, 22.3 – < 22.3R2-S2, 22.3R3, 22.4 – < 22.4R2-S1, 22.4R3 20.4R3-S8

Public exploits

Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.

Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.

GitHub 1 repository

Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.

Advisories 1

References