CVE-2007-1625 in realGuestbook
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in save_entry.php in realGuestbook 5.01 allows remote attackers to inject arbitrary web script or HTML via the homepage parameter, as reachable through add_entry.php. NOTE: the original report stated that the vulnerability was in add_entry.php, which does not receive the input data.
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Analysis
by VulDB Data Team • 08/27/2018
The vulnerability described in CVE-2007-1625 represents a classic cross-site scripting flaw within the realGuestbook 5.01 web application, specifically targeting the save_entry.php component. This type of vulnerability falls under the Common Weakness Enumeration category CWE-79, which defines improper neutralization of input during web page generation as a fundamental weakness in web application security. The flaw manifests when user-supplied data from the homepage parameter is not properly sanitized or validated before being stored and subsequently rendered back to users. The attack vector is particularly concerning because it originates from the add_entry.php page which serves as the initial interface for guestbook entries, but the actual vulnerability resides in the save_entry.php script that processes and stores the submitted data.
The technical execution of this XSS attack occurs through the manipulation of the homepage parameter which is passed from the add_entry.php form to the save_entry.php handler. When attackers submit malicious script code through this parameter, the application fails to implement adequate input validation or output encoding mechanisms. The vulnerable code path allows arbitrary HTML and JavaScript to be injected directly into the application's database storage, where it remains dormant until retrieved and displayed to other users. This creates a persistent XSS scenario where any user visiting pages that render the stored malicious content becomes a potential victim of the attack.
The operational impact of this vulnerability extends beyond simple data theft or defacement, as it enables attackers to execute malicious code within the context of other users' browsers. This capability allows for session hijacking, credential theft, redirection to malicious sites, and potentially full compromise of user accounts. The vulnerability affects all users who access the guestbook application, making it particularly dangerous in environments where the application serves as a public-facing interface. The fact that the original reporting incorrectly identified add_entry.php as the vulnerable component highlights the complexity of web application security analysis and the importance of thorough code review processes that can trace data flow through multiple interconnected scripts.
Mitigation strategies for this vulnerability must address both the immediate code-level fixes and broader architectural security considerations. The primary remediation involves implementing strict input validation and output encoding practices, ensuring that all user-supplied data undergoes proper sanitization before being stored in the database. This includes applying HTML entity encoding to any content that will be rendered back to users, implementing Content Security Policy headers, and conducting comprehensive input validation to reject potentially malicious payloads. Organizations should also consider implementing web application firewalls and regular security scanning to detect similar vulnerabilities in other applications. The vulnerability demonstrates the critical importance of proper input handling and the principle of least privilege in web application design, aligning with ATT&CK technique T1059.007 for scripting and T1566.001 for spearphishing with malicious attachments in phishing campaigns that might exploit such flaws.