CVE-2007-6377 in BadBlue
Summary
by MITRE
Stack-based buffer overflow in the PassThru functionality in ext.dll in BadBlue 2.72b and earlier allows remote attackers to execute arbitrary code via a long query string.
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Analysis
by VulDB Data Team • 10/13/2024
The vulnerability identified as CVE-2007-6377 represents a critical stack-based buffer overflow flaw within the PassThru functionality of BadBlue web server software version 2.72b and earlier. This vulnerability exists in the ext.dll component and specifically affects the handling of query strings during HTTP request processing. The flaw arises from inadequate input validation and bounds checking within the software's memory management routines, creating an exploitable condition where maliciously crafted input can overwrite adjacent memory locations on the stack.
The technical implementation of this vulnerability demonstrates a classic buffer overflow scenario where a query string exceeding the allocated buffer size in the PassThru functionality triggers memory corruption. When the web server processes a malformed HTTP request containing an excessively long query parameter, the software fails to properly validate the input length before copying it into a fixed-size stack buffer. This allows attackers to overwrite return addresses, function pointers, and other critical stack data structures, potentially enabling arbitrary code execution with the privileges of the web server process. The vulnerability is particularly concerning as it operates over network protocols and can be exploited remotely without authentication requirements.
From an operational impact perspective, this vulnerability presents a severe risk to organizations utilizing vulnerable BadBlue installations, as it allows remote code execution capabilities that could lead to complete system compromise. Attackers could leverage this vulnerability to gain unauthorized access to web servers, potentially escalating privileges to system level access, and using the compromised server as a launching point for further attacks within the network infrastructure. The attack surface is particularly broad as the vulnerability affects the core web serving functionality and can be exploited through standard HTTP GET requests containing maliciously crafted query strings.
Security professionals should note that this vulnerability aligns with CWE-121 Stack-based Buffer Overflow, which is categorized under the broader category of memory safety issues in software development. The exploitability characteristics of this vulnerability are consistent with ATT&CK technique T1059.007 Command and Scripting Interpreter: PowerShell, as attackers may use the compromised system to execute malicious PowerShell commands or other payloads. Organizations should implement immediate mitigations including updating to patched versions of BadBlue software, implementing network-based restrictions to limit access to vulnerable systems, and deploying intrusion detection systems to monitor for exploitation attempts. Additionally, input validation controls should be implemented at network boundaries to filter out suspicious query strings that exceed normal length parameters. The vulnerability serves as a reminder of the critical importance of proper memory management practices and input validation in web server software development, particularly in environments where remote code execution capabilities could be leveraged for unauthorized access to sensitive systems and data.