CVE-2005-0570 in PunBB
Summary
by MITRE
profile.php in PunBB 1.2.1 allows remote attackers to cause a denial of service (account lockout) by setting the user s password to NULL.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 05/31/2019
The vulnerability described in CVE-2005-0570 affects PunBB version 1.2.1 and represents a significant security flaw in the forum software's user authentication handling mechanism. This issue resides within the profile.php script which manages user profile modifications, specifically the password update functionality. The vulnerability enables remote attackers to exploit a logic flaw in the password validation process that allows them to set a user's password to a NULL value, thereby effectively locking out legitimate users from their accounts. This type of vulnerability falls under the category of authentication bypass and account compromise scenarios that can severely impact user access and system integrity.
The technical implementation of this flaw stems from inadequate input validation and sanitization within the password update routine. When an attacker submits a NULL value as a password through the profile.php interface, the system fails to properly validate this input, allowing the NULL value to be stored in the database. This creates a condition where the user account becomes inaccessible because the system cannot authenticate users with NULL passwords, effectively performing a denial of service attack against legitimate users. The vulnerability demonstrates poor security practices in input handling and represents a classic case of insufficient data validation that can be exploited through remote code execution or manipulation of user accounts.
The operational impact of this vulnerability extends beyond simple account lockout scenarios and can result in significant disruption to forum services and user experience. When legitimate users encounter account lockout situations due to this vulnerability, they may be unable to access their accounts, post content, or participate in forum discussions. From a security perspective, this vulnerability creates potential for abuse where attackers can systematically lock out multiple user accounts, making the forum unusable for its intended community. The attack vector is particularly concerning as it requires no authentication from the attacker, making it a low-effort, high-impact vulnerability that can be exploited by anyone with access to the forum's public interface.
Mitigation strategies for this vulnerability should focus on implementing robust input validation and sanitization practices within the application's authentication subsystem. System administrators should immediately apply security patches or upgrade to newer versions of PunBB that address this specific flaw. The fix should include validation checks that prevent NULL or empty password values from being accepted during profile updates, along with proper error handling that rejects invalid password submissions. Additionally, implementing proper access controls and monitoring for unusual account modification patterns can help detect and prevent exploitation attempts. This vulnerability aligns with CWE-20, which addresses improper input validation, and represents a clear violation of the principle of least privilege and secure coding practices. Organizations should also consider implementing multi-factor authentication mechanisms and account lockout policies to provide additional defense-in-depth against similar account compromise scenarios. The ATT&CK framework would categorize this vulnerability under privilege escalation and credential access tactics, emphasizing the need for comprehensive security measures that protect user authentication systems from manipulation.