CVE-2004-0393 in rlpr daemon
Summary
by MITRE
format string vulnerability in the msg function for rlpr daemon (rlprd) 2.0.4 allows remote attackers to execute arbitrary code via format string specifiers in a buffer that can not be resolved which is provided to the syslog function.
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Analysis
by VulDB Data Team • 12/31/2024
The vulnerability identified as CVE-2004-0393 represents a critical format string vulnerability within the rlpr daemon version 2.0.4, specifically affecting the msg function implementation. This daemon serves as a print server component that processes print jobs and communicates with remote systems, making it a potential attack vector for malicious actors seeking unauthorized system access. The flaw arises from improper input validation and handling within the syslog function call, where user-supplied data containing format specifiers is directly processed without adequate sanitization. The vulnerability manifests when the rlprd daemon receives a buffer containing unresolved format string specifiers that are subsequently passed to the syslog function, creating an exploitable condition that can be leveraged for arbitrary code execution.
The technical exploitation of this vulnerability occurs through the manipulation of input parameters that are processed by the msg function, which then forwards these parameters to the syslog function without proper validation. When the syslog function encounters format specifiers such as %s, %d, or %x within the user-provided buffer, it attempts to interpret these as instructions for retrieving data from memory locations rather than treating them as literal text. This behavior enables attackers to craft malicious input that can lead to information disclosure, stack corruption, or direct code execution depending on the specific implementation details and memory layout. The vulnerability is classified as a format string vulnerability under CWE-134, which specifically addresses the improper use of format strings in applications that handle user input.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it allows remote attackers to execute arbitrary code with the privileges of the rlprd daemon process, typically running with elevated system permissions. Attackers can leverage this weakness to gain unauthorized access to the system, potentially leading to complete system compromise, data exfiltration, or the establishment of persistent backdoors. The remote nature of the attack means that exploitation can occur from any network location without requiring local system access, making it particularly dangerous for networked environments. This vulnerability directly aligns with ATT&CK technique T1059.007 for Command and Scripting Interpreter, as successful exploitation would enable attackers to execute arbitrary commands on the affected system.
Mitigation strategies for CVE-2004-0393 should focus on immediate patching of the rlprd daemon to a version that properly validates and sanitizes input before passing it to syslog functions. Organizations should implement network segmentation to limit access to print server functionality and disable unnecessary print services where possible. Input validation measures including strict parameter sanitization and the use of safe string functions that prevent format string interpretation should be implemented. Additionally, monitoring systems should be configured to detect unusual patterns of print job submissions that might indicate exploitation attempts. The vulnerability highlights the importance of following secure coding practices and adhering to standards such as those outlined in the CWE database and ATT&CK framework for preventing similar issues in future software development cycles. Regular security assessments and vulnerability scanning should be conducted to identify and remediate similar weaknesses in other network services and applications.