CVE-2006-1279 in Cgi Session
Summary
by MITRE
CGI::Session 4.03-1 allows local users to overwrite arbitrary files via a symlink attack on temporary files used by (1) Driver::File, (2) Driver::db_file, and possibly (3) Driver::sqlite.
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Analysis
by VulDB Data Team • 09/09/2017
The vulnerability described in CVE-2006-1279 represents a critical file system security flaw affecting CGI::Session version 4.03-1 and earlier implementations. This issue manifests as a symlink attack that enables local users to overwrite arbitrary files through improper handling of temporary files within the session management framework. The vulnerability specifically impacts three driver components: Driver::File, Driver::db_file, and potentially Driver::sqlite, all of which utilize temporary file creation mechanisms that lack proper security checks.
The technical flaw stems from insufficient validation of temporary file creation processes within the CGI::Session library. When these drivers create temporary files to store session data, they do not properly verify that the target file paths are not symbolic links or do not point to existing files that could be overwritten. This weakness allows an attacker with local access to manipulate the file system by creating malicious symbolic links in strategic locations, thereby enabling them to overwrite files with arbitrary content. The vulnerability is classified under CWE-377 as "Insecure Temporary File Creation" and aligns with CWE-59 with "Improper Link Resolution Before File Access" which specifically addresses the dangers of symbolic link manipulation in file operations.
The operational impact of this vulnerability is significant for systems running affected versions of CGI::Session, particularly those with web applications that rely on session management. Local attackers can exploit this weakness to overwrite critical system files, configuration files, or even executable binaries, potentially leading to privilege escalation, data corruption, or complete system compromise. The attack vector requires local system access but can be particularly dangerous in multi-user environments where attackers might gain access through compromised user accounts or shared system resources. This vulnerability directly relates to ATT&CK technique T1059.007 for "Command and Scripting Interpreter: Unix Shell" and T1078.004 for "Valid Accounts: Default Accounts" as attackers may leverage compromised local accounts to execute the symbolic link attacks.
Mitigation strategies for this vulnerability require immediate patching of the CGI::Session library to version 4.04 or later, which includes proper temporary file handling mechanisms that prevent symlink attacks. System administrators should also implement proper file system permissions and access controls to limit local user privileges, particularly for directories where temporary files might be created. Additional protective measures include monitoring for suspicious file creation patterns, implementing proper file system auditing, and ensuring that temporary file directories have restrictive permissions. The vulnerability demonstrates the importance of secure temporary file handling practices and aligns with security best practices outlined in NIST SP 800-128 for temporary file security and OWASP Top Ten security controls for preventing file system attacks. Organizations should conduct comprehensive vulnerability assessments to identify all instances of the affected library and ensure proper patch management protocols are in place to prevent similar issues in other components of their web application infrastructure.