Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Network-reachable upload requiring a privileged backend account (PR:H) with low complexity; RCE breaks out of the app to the host, so scope changes (S:C) with full C/I/A impact.
Primary rating from Vendor (Joomla).
CVSS VectorVendor: Joomla
Lifecycle Timeline
2DescriptionCVE.org
The Joomla extension JMedia is vulnerable to an authenticated arbitrary file upload, leading to RCE. Executable uploads/writes possible (incl. polyglot filenames); chmod didn't strip execute bits.
AnalysisAI
Authenticated arbitrary file upload in the ThemeXpert JMedia media-manager extension for Joomla lets an authenticated privileged user (PR:H) write executable files to the server and achieve remote code execution. Uploads accept executable content and polyglot filenames, and the extension's chmod handling fails to strip execute bits, so a planted file can be directly invoked by the web server. Rated CVSS 4.0 9.4 (Critical); no public exploit identified at time of analysis and it is not listed in CISA KEV.
Technical ContextAI
JMedia is a media-management extension for the Joomla CMS (CPE cpe:2.3:a:themexpert.com:jmedia_extension_for_joomla). The root cause is CWE-434 (Unrestricted Upload of File with Dangerous Type): the upload handler does not adequately restrict file type or content, permitting server-side scripts (e.g. PHP) to be written into a web-accessible location. Two compounding weaknesses are called out - polyglot filenames that evade naming/extension checks, and a chmod routine that does not strip execute bits - so an uploaded artifact retains executable permissions and can be requested and run by the PHP/Apache-Nginx stack serving Joomla.
RemediationAI
No vendor-released patch version is identified at time of analysis, and the sole reference (https://www.themexpert.com/joomla-extensions/joomla-media-manager) is a product page rather than an advisory, so confirm the latest release and any changelog directly with ThemeXpert before upgrading. Because PR:H access is required, the strongest compensating controls target account exposure and file execution: restrict and audit Joomla backend accounts that hold media-upload privileges, enforce strong/MFA-backed admin authentication, and place the /administrator interface behind an IP allowlist or VPN (trade-off: remote admins lose direct access). At the web-server layer, deny execution of scripts within Joomla media/upload directories - e.g. an Apache 'php_admin_flag engine off' / removing handler mappings or an Nginx location block that returns 403 for .php under the upload path (trade-off: breaks any legitimate scripts placed there) - and ensure the OS mount or directory is not marked executable. A WAF rule blocking upload of executable/polyglot content adds defense but can be bypassed and should not be the sole control.
More in Jmedia Extension For Joomla
View allStored and reflected cross-site scripting in ThemeXpert's JMedia media-manager extension for Joomla lets an attacker upl
Server-Side Request Forgery in the JMedia Extension for Joomla (themexpert.com) allows authenticated administrators to d
Same technique File Upload
View allShare
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-46054
GHSA-3qgh-5pfw-cjfw