CVE-2017-9756 in binutils
Summary
by MITRE
The aarch64_ext_ldst_reglist function in opcodes/aarch64-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 • 12/04/2024
The vulnerability identified as CVE-2017-9756 represents a critical buffer overflow flaw within the GNU Binutils 2.28 package, specifically within the aarch64_ext_ldst_reglist function located in the opcodes/aarch64-dis.c file. This issue manifests when processing crafted 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 exists in the disassembly component of binutils, which is widely used for analyzing and debugging binary code across various architectures including ARM64. The vulnerability affects systems that utilize the GNU binutils suite for reverse engineering, debugging, and binary analysis tasks, making it particularly concerning for security researchers, developers, and system administrators who rely on these tools for legitimate purposes. The buffer overflow occurs during the parsing of AArch64 instruction sets, specifically when handling register list operations in the disassembly process.
The technical implementation of this vulnerability stems from inadequate bounds checking within the aarch64_ext_ldst_reglist function, which processes register list operations during instruction decoding. When a maliciously crafted binary contains specially constructed AArch64 instructions with malformed register list specifications, the function fails to properly validate input parameters before performing memory operations. This lack of input validation leads to a classic buffer overflow condition where data is written beyond the allocated memory boundaries of the target buffer. The flaw is particularly dangerous because it can be triggered through normal operation of objdump when analyzing seemingly benign binary files, making it difficult to predict and prevent. The vulnerability is classified under CWE-121, which describes heap-based buffer overflow conditions, and the attack surface is expanded through the ATT&CK framework's T1059.007 technique for executing malicious code through command-line interfaces. The overflow can potentially lead to application crashes, resulting in denial of service conditions, but the unspecified other impacts suggest potential for more severe consequences including arbitrary code execution or information disclosure.
The operational impact of CVE-2017-9756 extends beyond simple denial of service scenarios, affecting the reliability and security posture of systems that depend on GNU binutils for binary analysis. Attackers can exploit this vulnerability by preparing malicious binary files that, when processed by objdump, trigger the buffer overflow condition and cause system instability. The vulnerability affects a wide range of systems including development environments, security analysis platforms, and automated build systems where objdump is commonly used. Organizations relying on automated security scanning tools or continuous integration pipelines that invoke objdump may experience unexpected system failures or crashes. The vulnerability also poses risks to forensic analysis environments where investigators might encounter malicious files during routine analysis, potentially leading to system compromise or data corruption. The impact is particularly severe in enterprise environments where multiple users may access shared analysis systems, as a single malicious file could affect the entire system or network. This vulnerability demonstrates the critical importance of input validation in security-sensitive code, especially in tools that process untrusted binary data and are widely deployed across different computing environments.
Mitigation strategies for CVE-2017-9756 should prioritize immediate patching of affected GNU binutils installations to version 2.29 or later, which contains the necessary fixes for the buffer overflow condition. System administrators should implement defensive measures including restricting access to objdump and other binutils utilities to trusted users only, and establishing proper input validation procedures for binary analysis workflows. Organizations should consider implementing sandboxed environments for processing untrusted binary files, isolating the analysis process from critical system resources. Network security controls such as intrusion detection systems should be configured to monitor for suspicious objdump usage patterns or file analysis activities that might indicate exploitation attempts. The vulnerability highlights the importance of maintaining up-to-date security toolchains and implementing proper software supply chain security measures. Regular security audits of development and analysis environments should include verification of binutils versions and patch status, while automated vulnerability scanning tools should be configured to detect and alert on outdated or vulnerable components. Additionally, implementing least privilege principles for binary analysis tools and establishing proper file handling procedures can significantly reduce the risk of exploitation. The remediation approach should also include comprehensive testing of patched systems to ensure that the vulnerability has been properly addressed without introducing regressions in functionality.