CVE-2017-9742 in binutils
Summary
by MITRE
The score_opcodes function in opcodes/score7-dis.c in GNU Binutils 2.28 allows remote attackers to cause a denial of service (buffer overflow and application crash) or possibly have unspecified other impact via a crafted binary file, as demonstrated by mishandling of this file during "objdump -D" execution.
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Analysis
by VulDB Data Team • 12/05/2024
The vulnerability identified as CVE-2017-9742 represents a critical buffer overflow flaw within the GNU Binutils 2.28 distribution, specifically affecting the score_opcodes function located in the opcodes/score7-dis.c file. This issue manifests when processing malformed binary files through the objdump utility with the -D flag, which disassembles object files and displays their contents in a human-readable format. The flaw stems from inadequate input validation and boundary checking within the disassembly engine, creating a condition where attacker-controlled data can overwrite adjacent memory locations beyond the intended buffer boundaries. The vulnerability operates at the intersection of software security and binary analysis, affecting tools that are fundamental to system administration, reverse engineering, and software development processes. This weakness directly impacts the integrity of the disassembly process and can be exploited to disrupt normal system operations through controlled memory corruption.
The technical exploitation of this vulnerability occurs when the score_opcodes function processes a crafted binary file that contains malformed opcode data or unexpected instruction sequences. During execution of objdump -D on such malicious input, the function fails to properly validate the size or structure of incoming data, leading to memory corruption that can result in immediate application termination or more subtle behavioral changes. The buffer overflow condition arises from improper handling of data structures within the disassembler's opcode scoring mechanism, where fixed-size buffers are written to without adequate bounds checking. This flaw aligns with CWE-121, which categorizes heap-based buffer overflows, and demonstrates how insufficient input validation in binary analysis tools can create dangerous attack surfaces. The vulnerability's impact extends beyond simple denial of service, as the memory corruption could potentially be leveraged for more sophisticated exploitation techniques, though the immediate effect is primarily application crash and service disruption.
The operational impact of CVE-2017-9742 is significant within environments that rely heavily on GNU Binutils for system administration, security analysis, and software development workflows. When exploited, this vulnerability can cause unauthorized service disruption across multiple systems that utilize objdump or related disassembly tools for debugging, reverse engineering, or security auditing purposes. The vulnerability is particularly dangerous in automated environments where binary file processing occurs without manual verification, as a single malicious file could trigger widespread system instability. Attackers can exploit this weakness by crafting specially formatted binary files that, when processed by objdump -D, cause the application to crash or behave unpredictably. From an adversarial perspective, this vulnerability maps to ATT&CK technique T1059.007, which involves the use of system binaries for execution, and T1499.004, which encompasses network denial of service attacks through system resource exhaustion. The flaw affects systems across multiple operating systems that include GNU Binutils, making it a widespread concern for security practitioners managing diverse computing environments.
Mitigation strategies for CVE-2017-9742 focus on both immediate patching and operational security measures to prevent exploitation. The primary solution involves upgrading to GNU Binutils version 2.29 or later, where the buffer overflow has been addressed through proper input validation and boundary checking mechanisms. System administrators should prioritize patching across all environments where objdump or similar disassembly tools are deployed, particularly in security-sensitive contexts where binary analysis is performed on untrusted inputs. Additionally, operational security measures should include implementing input sanitization for binary files processed through disassembly tools, employing sandboxing techniques for untrusted binary analysis, and monitoring for unusual objdump execution patterns that might indicate exploitation attempts. Organizations should also consider implementing file type validation and access controls to limit the execution of objdump against potentially malicious files, while maintaining regular security updates to address similar vulnerabilities in other components of the software supply chain. These measures align with security best practices outlined in NIST SP 800-128 and ISO/IEC 27001 frameworks for vulnerability management and incident response.