CVE-2012-5497 in Plone
Summary
by MITRE
membership_tool.py in Plone before 4.2.3 and 4.3 before beta 1 allows remote attackers to enumerate user account names via a crafted URL.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 03/29/2022
The vulnerability identified as CVE-2012-5497 affects Plone content management systems prior to versions 4.2.3 and 4.3 beta 1, specifically within the membership_tool.py component. This flaw represents a critical information disclosure vulnerability that enables remote attackers to systematically enumerate valid user account names through the manipulation of crafted URLs. The vulnerability stems from insufficient input validation and access control mechanisms within the membership tool's URL handling functionality, creating an attack vector that directly compromises user account confidentiality.
The technical implementation of this vulnerability occurs when the membership_tool.py script processes user requests without proper authorization checks or input sanitization. Attackers can construct specific URLs that trigger the system to return information about user accounts, including usernames, without requiring authentication or proper access rights. This occurs because the system fails to properly validate the parameters passed in the URL, allowing malicious users to probe the system's user directory and systematically discover valid account names through response variations. The vulnerability is categorized under CWE-200 Information Exposure, specifically relating to improper information access control and insufficient input validation.
The operational impact of CVE-2012-5497 is significant for organizations relying on Plone systems, as it enables attackers to build comprehensive user account dictionaries that can facilitate subsequent attacks. Once valid usernames are discovered, attackers can proceed with password spraying, brute force attacks, or social engineering campaigns targeting specific user accounts. This vulnerability directly violates the principle of least privilege and information hiding, as it exposes user account information that should remain confidential. The attack can be automated and executed without requiring any special privileges or credentials, making it particularly dangerous for systems with public-facing user directories or authentication interfaces.
Organizations affected by this vulnerability should immediately upgrade to Plone versions 4.2.3 or later, or 4.3 beta 1 and newer, where the membership_tool.py has been patched to properly validate URL parameters and enforce appropriate access controls. Additional mitigations include implementing rate limiting on user enumeration endpoints, configuring proper firewall rules to restrict access to membership tools, and monitoring for suspicious URL patterns in web server logs. The vulnerability aligns with ATT&CK technique T1087.001 Account Discovery and T1566 Credential Access, as it enables attackers to gather information about valid accounts that can be leveraged for further compromise. Security teams should also conduct thorough audits of all membership and authentication-related components to identify similar vulnerabilities in custom implementations or third-party extensions that may be susceptible to similar information disclosure attacks.