CVE-2008-7007 in PHP VX Guestbook
Summary
by MITRE
Free PHP VX Guestbook 1.06 allows remote attackers to bypass authentication and gain administrative access by setting the (1) admin_name and (2) admin_pass cookie values to 1.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 11/04/2024
This vulnerability exists in Free PHP VX Guestbook version 1.06, a web application designed for managing guestbook entries. The flaw represents a critical authentication bypass issue that allows remote attackers to escalate privileges without proper credentials. The vulnerability stems from improper input validation and authentication mechanisms within the application's cookie handling system. When attackers manipulate the admin_name and admin_pass cookie values to equal 1, the application incorrectly interprets these values as valid administrative credentials, thereby granting unauthorized access to the administrative interface.
The technical implementation of this vulnerability demonstrates a classic insecure comparison flaw where the application performs a simple equality check rather than proper authentication verification. This type of vulnerability falls under CWE-287 which addresses improper handling of authentication tokens and credentials. The weakness lies in the application's trust of user-supplied cookie values without proper validation or sanitization. Attackers can exploit this by simply setting two specific cookies with the value 1, bypassing all legitimate authentication mechanisms and gaining full administrative control over the guestbook system.
The operational impact of this vulnerability is severe as it provides complete unauthorized access to the administrative functions of the guestbook application. An attacker could modify guestbook entries, delete content, add malicious entries, access sensitive data, or potentially use the administrative interface to install malware or establish persistent access. This vulnerability affects any system running the vulnerable version of Free PHP VX Guestbook, making it particularly dangerous in shared hosting environments or web applications with multiple users. The remote nature of the attack means that exploitation can occur from anywhere on the internet without requiring physical access or local system compromise.
The recommended mitigations for this vulnerability involve immediate patching of the Free PHP VX Guestbook application to version 1.07 or later, which contains the necessary authentication fixes. Organizations should also implement proper input validation for all cookie values and employ secure authentication mechanisms that do not rely on simple value comparisons. Network segmentation and monitoring of cookie values can help detect exploitation attempts. Additionally, implementing web application firewalls and conducting regular security assessments can help identify similar vulnerabilities in other applications. This vulnerability aligns with ATT&CK technique T1078 which covers valid accounts and privilege escalation through authentication bypass methods. The flaw demonstrates the importance of proper authentication design and input validation in preventing unauthorized access to administrative functions.