CVE-2005-1626 in Pico Server
Summary
by MITRE
Multiple buffer overflows in handlers.c for Pico Server (pServ) before 3.3 may allow attackers to execute arbitrary code.
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Analysis
by VulDB Data Team • 07/24/2017
The vulnerability identified as CVE-2005-1626 represents a critical security flaw affecting Pico Server versions prior to 3.3, specifically within the handlers.c component of the software. This issue manifests as multiple buffer overflows that occur during the processing of incoming network requests, creating potential entry points for malicious actors to gain unauthorized system access. The vulnerability is particularly concerning because it affects the core request handling mechanisms of the web server, making it a prime target for exploitation attempts. Buffer overflows in server software typically arise when programs fail to properly validate input lengths before copying data into fixed-size memory buffers, leading to memory corruption that can be leveraged for code execution.
The technical implementation of this vulnerability stems from inadequate bounds checking within the Pico Server's request processing functions. When the server receives malformed HTTP requests or specially crafted input data, the handlers.c code fails to validate the length of incoming data before storing it in predetermined memory buffers. This allows attackers to overflow these buffers and overwrite adjacent memory locations, potentially including return addresses, function pointers, or other critical control data. The flaw exists in the server's protocol handling routines where user-supplied input is directly processed without proper sanitization measures, creating a pathway for attackers to manipulate program execution flow. This type of vulnerability is classified under CWE-121 as "Stack-based Buffer Overflow" and CWE-122 as "Heap-based Buffer Overflow" in the Common Weakness Enumeration catalog, which are fundamental categories representing the core nature of the memory corruption issue.
The operational impact of CVE-2005-1626 extends beyond simple denial of service scenarios, as successful exploitation can result in complete system compromise. Attackers who successfully exploit this vulnerability can execute arbitrary code with the privileges of the Pico Server process, which typically runs with elevated permissions on the target system. This could lead to unauthorized access to sensitive data, complete system takeover, or the installation of backdoors for persistent access. The vulnerability affects organizations using older versions of Pico Server, which were commonly deployed in enterprise environments during the mid-2000s era. The exploitation of such vulnerabilities aligns with tactics described in the MITRE ATT&CK framework under T1059 for Command and Scripting Interpreter and T1068 for Exploitation for Privilege Escalation, demonstrating how buffer overflows can be leveraged for broader attack objectives.
Mitigation strategies for this vulnerability primarily focus on immediate remediation through software updates and patches. Organizations should prioritize upgrading to Pico Server version 3.3 or later, which includes proper bounds checking and memory validation mechanisms. Additionally, network segmentation and firewall rules can help limit exposure by restricting access to the vulnerable server from untrusted networks. Input validation should be implemented at multiple layers including application-level filtering and network-based intrusion detection systems. Security monitoring should include detection of unusual request patterns that might indicate exploitation attempts, particularly focusing on malformed HTTP requests or unusually long input data. The vulnerability also underscores the importance of regular security assessments and vulnerability management programs, as outlined in ISO/IEC 27001 and NIST SP 800-53 security frameworks, which emphasize the need for continuous monitoring and timely patch deployment to prevent exploitation of known vulnerabilities.