CVE-2016-9838 Privilege escalation in n/a
Attackers can hijack registered user accounts and modify group mappings, usernames, and passwords via improper session data filtering in Joomla registration forms.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2016-9838?
CVE-2016-9838 is a high-severity vulnerability in Joomla Joomla\!, published on 16 Dec 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An issue was discovered in components/com_users/models/registration.php in Joomla! before 3.6.5. Incorrect filtering of registration form data stored to the session on a validation error enables a user to gain access to a registered user's account and reset the user's group mappings, username, and password, as demonstrated by submitting a form that targets the `registration.register` task.
Weakness: CWE-284
Which versions are affected by CVE-2016-9838?
It affects 1 product.
Products include Joomla Joomla\!.
How do I fix CVE-2016-9838?
No fix has been published for CVE-2016-9838 yet. Limit exposure of the affected software until one is available.
Is CVE-2016-9838 being exploited?
There is no known exploitation of CVE-2016-9838 in the wild and no public exploit code.
Public exploit code: 1 Exploit-DB entry and 1 proofs of concept on GitHub.
Other vulnerabilities in Joomla Joomla\!
- CVE-2016-10033 PHPMailer Command Injection
- CVE-2023-23752 Joomla! Improper Access Control
- CVE-2026-48902 Joomla! Core - [20260518] - Transport encryption downgrade for password and username reset links
- CVE-2025-25226 [20250401] - Joomla Framework - SQL injection vulnerability in quoteNameStr method of Database package
- CVE-2022-23795 [20220303] - Core - User row are not bound to a authentication mechanism
Sources
Also known as GHSA-r7gw-fgrc-gxxj.