CVE-2011-3343 in OpenTTD
Summary
by MITRE
Multiple buffer overflows in OpenTTD before 1.1.3 allow local users to cause a denial of service (daemon crash) or possibly gain privileges via (1) a crafted BMP file with RLE compression or (2) crafted dimensions in a BMP file.
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Analysis
by VulDB Data Team • 11/18/2021
The vulnerability described in CVE-2011-3343 represents a critical security flaw within the OpenTTD game engine, a popular open-source simulation game that allows players to build and manage transportation networks. This vulnerability affects versions prior to 1.1.3 and demonstrates the dangerous consequences that can arise from inadequate input validation in multimedia file processing components. The issue stems from the game's failure to properly validate bitmap file dimensions and compression parameters, creating exploitable conditions that can be leveraged by malicious actors to compromise system stability and potentially escalate privileges.
The technical implementation of this vulnerability involves two distinct attack vectors that exploit buffer overflow conditions within the image processing subsystem. The first vector occurs when processing BMP files with Run-Length Encoding (RLE) compression, where the application fails to validate the length of compressed data segments against allocated buffer boundaries. The second vector targets the parsing of BMP file headers, specifically the dimension fields that define the image width and height. When these values are crafted to exceed expected limits or contain malformed data, the application's memory management routines become vulnerable to overflow conditions that can corrupt adjacent memory regions. Both scenarios fall under the CWE-121 CWE category for stack-based buffer overflow conditions, where insufficient bounds checking allows attackers to overwrite critical memory locations.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable privilege escalation attacks within the affected system. When local users can trigger daemon crashes through malformed BMP files, they effectively gain the ability to disrupt service availability, which aligns with the ATT&CK technique T1499 for network denial of service. However, the more concerning aspect emerges when considering that buffer overflows in memory management components can often be exploited to execute arbitrary code, particularly when the vulnerable application runs with elevated privileges. The daemon process that hosts OpenTTD typically operates with sufficient permissions to access system resources, making successful exploitation potentially catastrophic for system integrity and availability.
Mitigation strategies for CVE-2011-3343 should prioritize immediate patch application to versions 1.1.3 and later, which contain the necessary input validation fixes. Organizations should implement comprehensive file validation protocols that verify all incoming bitmap files against strict parameter limits before processing, particularly focusing on dimension fields and compression type indicators. System administrators should also consider implementing privilege separation techniques where the game daemon operates with minimal required permissions, reducing the potential impact of successful exploitation attempts. Network-level defenses such as intrusion detection systems can monitor for suspicious file upload patterns, while endpoint protection solutions should be configured to scan multimedia files for known malicious indicators. The vulnerability also highlights the importance of following secure coding practices including bounds checking, memory allocation validation, and proper error handling in file processing components, as outlined in the OWASP Secure Coding Practices and the CERT Secure Coding Standards for C and C++ programming languages.