CVE-2001-1332 in CUPS
Summary
by MITRE
Buffer overflows in Linux CUPS before 1.1.6 may allow remote attackers to execute arbitrary code.
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Analysis
by VulDB Data Team • 04/30/2019
The vulnerability identified as CVE-2001-1332 represents a critical buffer overflow flaw affecting the Common Unix Printing System (CUPS) version 1.1.5 and earlier. This issue resides within the print server component of the Linux operating system, specifically within the cupsd daemon that handles printer communication and job processing. The buffer overflow vulnerability occurs when the system processes certain malformed input data from network requests, particularly during the handling of print job parameters and printer configuration data. The flaw is classified under CWE-121 as a stack-based buffer overflow, where insufficient bounds checking allows attackers to overwrite adjacent memory locations with malicious data. This vulnerability exists because the CUPS implementation fails to properly validate the length of input data received from remote clients, creating an exploitable condition that can be leveraged for arbitrary code execution. The attack surface is particularly concerning as CUPS typically runs with elevated privileges and accepts connections from remote hosts, making it a prime target for remote exploitation attempts.
The technical exploitation of this vulnerability requires an attacker to send specifically crafted print job requests or configuration data to the vulnerable CUPS service running on port 631. When the cupsd daemon processes these malformed inputs without proper bounds checking, the buffer overflow allows the attacker to overwrite the return address on the stack and redirect execution flow to malicious code injected into the buffer. This type of attack aligns with the MITRE ATT&CK framework under the technique T1059.007 for command and scripting interpreter, specifically targeting remote code execution through service exploitation. The vulnerability is particularly dangerous because it can be exploited remotely without requiring authentication, as the print server typically accepts connections from any client on the network. The buffer overflow can be triggered through various input parameters including printer names, job titles, or document formats that are not properly sanitized before processing. This flaw demonstrates a classic security weakness in the input validation process where the system assumes that all incoming data is trustworthy and does not perform adequate length checking or memory boundary enforcement.
The operational impact of CVE-2001-1332 extends beyond simple code execution, as successful exploitation can lead to complete system compromise and persistent access for attackers. An attacker who successfully exploits this vulnerability can gain root privileges on the affected system, enabling them to install backdoors, modify system files, steal sensitive data, or use the compromised system as a launching point for further attacks within the network. The vulnerability affects organizations that rely on CUPS for printer management, particularly those with networked printers and print servers that are accessible from external networks. The attack can result in unauthorized access to print jobs, potential data leakage through printer queues, and disruption of legitimate printing services. Organizations with multiple print servers or those using older versions of CUPS across their network infrastructure face significant risk exposure, as the vulnerability can be exploited at scale without requiring specialized knowledge of the target systems. The security implications are further exacerbated by the fact that many organizations may not regularly update their print server software, leaving these systems vulnerable to exploitation for extended periods.
Mitigation strategies for CVE-2001-1332 require immediate action to patch the vulnerable CUPS version with the security update released in version 1.1.6. Organizations should implement network segmentation to restrict access to print servers, ensuring that only authorized clients can connect to port 631. The recommended approach includes configuring firewalls to block external access to the print server port and implementing access controls that limit which hosts can submit print jobs. Additionally, system administrators should disable unnecessary print server features and ensure that the cupsd daemon runs with minimal required privileges. Network monitoring should be enhanced to detect unusual print job patterns or unauthorized access attempts that might indicate exploitation attempts. The vulnerability highlights the importance of regular software updates and vulnerability management processes, as this issue was resolved in a security patch released by the CUPS development team. Organizations should also consider implementing intrusion detection systems that can identify and alert on potential buffer overflow exploitation attempts. The remediation process involves not only updating the CUPS software but also conducting thorough vulnerability assessments to identify any other potentially vulnerable services or applications that may have similar input validation weaknesses, as this represents a common class of security flaws that should be addressed through comprehensive security hardening practices.