CVE-2018-12071 CodeIgniter Session Fixation Vulnerability

Critical 9.8 Published 17 Jun 2018 Updated 9 Jun 2025

Attackers can hijack user sessions in CodeIgniter applications due to improper session fixation protection, leading to account takeover.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2018-12071?

CVE-2018-12071 is a critical authentication bypass vulnerability in n/a, published on 17 Jun 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A Session Fixation issue exists in CodeIgniter before 3.1.9 because session.use_strict_mode in the Session Library was mishandled.

Weakness: CWE-384

Which versions are affected by CVE-2018-12071?

2 open source packages ship an affected version, including codeigniter/framework. It affects 1 product.

Package	Affected	Fixed in
`codeigniter/framework` Packagist	All versions	`3.1.10`
`codeigniter/framework` Packagist	All versions	`3.1.10`

Products include Codeigniter Codeigniter.

How do I fix CVE-2018-12071?

Upgrade codeigniter/framework to 3.1.10 or later.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2018-12071 being exploited?

There is no known exploitation of CVE-2018-12071 in the wild and no public exploit code.

Sources

Also known as GHSA-g434-3q2j-hj4r.