CVE-2005-0077 in Red Hat
Summary
by MITRE
The DBI library (libdbi-perl) for Perl allows local users to overwrite arbitrary files via a symlink attack on a temporary PID file.
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Analysis
by VulDB Data Team • 05/29/2019
The vulnerability described in CVE-2005-0077 affects the DBI library implementation in Perl, specifically targeting the libdbi-perl package. This issue represents a classic symlink attack scenario that exploits improper handling of temporary files during the library's operation. The vulnerability resides in how the library manages its temporary PID file, creating a window of opportunity for local attackers to manipulate file system permissions and overwrite arbitrary files on the system. The flaw demonstrates a fundamental security weakness in the library's temporary file creation process, where the system fails to properly validate or secure the temporary file path before writing to it.
The technical implementation of this vulnerability stems from the library's failure to use secure temporary file creation methods. When the DBI library creates a PID file for process identification, it does not adequately verify that the target file path is not a symbolic link to another location on the file system. This allows an attacker who controls the symbolic link to redirect the library's write operations to any location they choose, potentially overwriting critical system files or configuration data. The vulnerability operates at the file system level where the library performs a race condition between creating a temporary file and then writing to it, without proper atomic operations or file path validation.
From an operational perspective, this vulnerability presents a significant risk to systems running applications that depend on the DBI library for database connectivity. Local attackers with minimal privileges can exploit this weakness to escalate their access or cause system instability by overwriting important files. The impact extends beyond simple file overwrite scenarios, as attackers could potentially target system configuration files, log files, or even binary executables to achieve further compromise. This vulnerability particularly affects Unix-like systems where symbolic link manipulation is possible and where the DBI library is commonly used in web applications and database-driven services.
The security implications of this vulnerability align with CWE-377, which addresses insecure temporary file handling, and can be mapped to ATT&CK technique T1059 for privilege escalation through local exploitation. Organizations should implement immediate mitigations including updating to patched versions of the libdbi-perl package, implementing proper file system permissions, and monitoring for unauthorized symbolic link creation in temporary directories. System administrators should also consider implementing additional security controls such as file integrity monitoring and restricting write permissions in temporary file locations to prevent similar vulnerabilities from being exploited in other software components that may exhibit similar insecure temporary file handling patterns.