e107inc e107 up to 2.3.6 Installer install.php unserialize previous_steps deserialization

Summaryinfo

A vulnerability, which was classified as critical, was found in e107inc e107 up to 2.3.6. Impacted is the function unserialize of the file install.php of the component Installer. The manipulation of the argument previous_steps results in deserialization. This vulnerability is reported as CVE-2026-55573. The attack can be launched remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in e107inc e107 up to 2.3.6. Affected is the function unserialize of the file install.php of the component Installer. The manipulation of the argument previous_steps with an unknown input leads to a deserialization vulnerability. CWE is classifying the issue as CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

e107 is a content management system (CMS). Prior to 2.3.7, install.php decodes the attacker-controlled previous_steps POST parameter and passes it to unserialize() at file scope and again in the e_install constructor without restricting allowed classes. The installer remains accessible after a normal installation, and a crafted object graph using the bundled GuzzleHttp\Psr7\PumpStream class can flow through paths.hash into site_path, where string coercion invokes an attacker-controlled callable. An unauthenticated attacker who can reach install.php can therefore execute arbitrary PHP functions with the web server process's privileges, leading to full server compromise. This issue is fixed in version 2.3.7.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-55573 since 06/17/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are known, but there is no available exploit.

By approaching the search of inurl:install.php it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 2.3.7 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Content Management System

Vendor

• e107inc

Name

• e107

Version

• 2.3.0
• 2.3.1
• 2.3.2
• 2.3.3
• 2.3.4
• 2.3.5
• 2.3.6

License

• open-source

Website

• Product: https://github.com/e107inc/e107/

CPE 2.3info

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CPE 2.2info

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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