CVE-2012-2667 in Symfony
Summary
by MITRE
Session fixation vulnerability in lib/user/sfBasicSecurityUser.class.php in SensioLabs Symfony before 1.4.18 allows remote attackers to hijack web sessions via vectors related to the regenerate method and unspecified "database backed session classes."
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 12/03/2021
The vulnerability described in CVE-2012-2667 represents a critical session fixation weakness within the Symfony web application framework's security implementation. This flaw exists in the sfBasicSecurityUser.class.php file, which serves as a foundational component for user authentication and session management in Symfony applications. The issue specifically affects Symfony versions prior to 1.4.18, making it a significant concern for organizations running outdated framework versions. Session fixation vulnerabilities occur when an application fails to properly invalidate or regenerate session identifiers upon user authentication, creating opportunities for attackers to exploit established session tokens.
The technical nature of this vulnerability stems from improper session handling during the regenerate method execution within database-backed session classes. When users authenticate within Symfony applications, the framework should generate a new, unique session identifier to prevent attackers from hijacking active sessions. However, the flawed implementation in affected versions allows session tokens to remain consistent or predictable across authentication boundaries. This weakness enables remote attackers to capture valid session identifiers and reuse them to impersonate legitimate users, effectively bypassing authentication mechanisms. The vulnerability is particularly dangerous because it operates at the core session management layer, affecting the fundamental security guarantees that web applications should provide.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it can lead to complete account compromise and data breaches. Attackers exploiting this flaw can maintain persistent access to user accounts, potentially gaining access to sensitive information, modifying data, or performing unauthorized transactions. The remote nature of the attack means that adversaries do not require physical access to systems or network proximity to exploit the vulnerability. This makes the attack surface particularly broad, as any user with access to the vulnerable application can be targeted. The database-backed session classes mentioned in the description suggest that the vulnerability affects applications using persistent session storage mechanisms, which are common in production environments where session data needs to persist across server restarts.
Organizations should immediately upgrade to Symfony 1.4.18 or later versions to address this vulnerability, as no effective workarounds exist for the underlying implementation flaw. Security teams should conduct comprehensive audits of their Symfony applications to identify all instances running vulnerable versions and prioritize remediation efforts. The vulnerability aligns with CWE-384, which specifically addresses session fixation issues in web applications, and represents a clear violation of security best practices outlined in OWASP Top 10. From an attack framework perspective, this vulnerability maps to techniques in the credential access and privilege escalation domains of the MITRE ATT&CK framework, where adversaries seek to maintain persistent access through session token manipulation. Network administrators should monitor for suspicious authentication patterns and implement additional logging mechanisms to detect potential exploitation attempts. The incident highlights the critical importance of keeping web application frameworks updated and demonstrates how fundamental security controls can be compromised through implementation flaws in core components.