CVE-2009-1576 in Drupal
Summary
by MITRE
Unspecified vulnerability in Drupal 5.x before 5.17 and 6.x before 6.11, as used in vbDrupal before 5.17.0, allows user-assisted remote attackers to obtain sensitive information by tricking victims into visiting the front page of the site with a crafted URL and causing form data to be sent to an attacker-controlled site, possibly related to multiple / (slash) characters that are not properly handled by includes/bootstrap.inc, as demonstrated using the search box. NOTE: this vulnerability can be leveraged to conduct cross-site request forgery (CSRF) attacks.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 09/03/2019
The vulnerability described in CVE-2009-1576 represents a critical information disclosure flaw affecting Drupal content management systems across multiple versions including 5.x before 5.17 and 6.x before 6.11, with impacted installations extending to vbDrupal versions prior to 5.17.0. This vulnerability stems from improper handling of multiple forward slash characters within the includes/bootstrap.inc file, creating a pathway for attackers to manipulate form data submission processes. The flaw specifically manifests when users are tricked into visiting a maliciously crafted URL that causes form data to be transmitted to an attacker-controlled domain, demonstrating the dangerous potential for user-assisted remote exploitation.
The technical implementation of this vulnerability leverages the improper parsing of URL paths containing multiple consecutive slash characters, which creates a condition where form data can be inadvertently directed to external domains rather than remaining within the intended application boundaries. This misconfiguration in the bootstrap.inc file allows attackers to craft URLs that, when accessed by unsuspecting users, trigger form submissions to attacker-controlled endpoints. The vulnerability is particularly concerning as it operates through a user-assisted attack vector where social engineering plays a crucial role in successful exploitation, making it difficult to defend against through traditional network security measures alone.
The operational impact of this vulnerability extends beyond simple information disclosure to encompass potential cross-site request forgery capabilities, as indicated in the CVE description. This dual nature means that attackers can not only obtain sensitive information but also potentially execute unauthorized actions on behalf of authenticated users. The vulnerability's exploitation requires minimal technical sophistication from attackers, as it relies on user interaction through crafted URLs that appear legitimate, making it particularly dangerous in environments where users frequently navigate between multiple websites. This flaw essentially undermines the integrity of form-based authentication and data submission processes within the affected Drupal installations.
Security practitioners should recognize this vulnerability as a variant of CWE-20, which addresses improper input validation, and it aligns with ATT&CK technique T1566 related to spearphishing with links. The remediation strategy centers on applying the official Drupal security patches available for versions 5.17 and 6.11, which address the specific path handling issues in bootstrap.inc. Organizations should also implement URL filtering mechanisms and user education programs to reduce the risk of successful social engineering attacks. Additionally, network monitoring should be enhanced to detect unusual form submission patterns to external domains, as this behavior would indicate potential exploitation attempts. The vulnerability demonstrates the critical importance of proper input sanitization and path validation in web application security, particularly in content management systems where user-generated content and form submissions are common components of normal operation.