CVE-2017-17123 in binutils
Summary
by MITRE
The coff_slurp_reloc_table function in coffcode.h in the Binary File Descriptor (BFD) library (aka libbfd), as distributed in GNU Binutils 2.29.1, allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via a crafted COFF based file.
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Analysis
by VulDB Data Team • 01/16/2023
The vulnerability identified as CVE-2017-17123 resides within the Binary File Descriptor (BFD) library, specifically in the coff_slurp_reloc_table function located in coffcode.h. This critical flaw affects GNU Binutils version 2.29.1 and represents a remote code execution risk that manifests as a denial of service condition. The BFD library serves as a fundamental component for handling various binary file formats including COFF, ELF, and others, making it a critical dependency for numerous development and system tools. When a maliciously crafted COFF file is processed by applications utilizing this library, the vulnerability becomes exploitable, potentially leading to system instability and application crashes.
The technical implementation of this vulnerability stems from inadequate input validation within the coff_slurp_reloc_table function. During the processing of relocation tables in COFF files, the function fails to properly validate pointer references, creating a condition where a NULL pointer dereference occurs when encountering malformed input data. This occurs because the function assumes certain data structures will contain valid pointers without proper verification, allowing attackers to craft COFF files with specifically designed relocation entries that trigger the NULL pointer access. The flaw operates at the binary parsing level, where the library's inability to handle malformed COFF structures results in immediate application termination. This type of vulnerability falls under CWE-476, which specifically addresses NULL pointer dereference conditions that can lead to system crashes and denial of service scenarios.
The operational impact of this vulnerability extends beyond simple application crashes, as it affects any system or application that relies on the BFD library for processing binary files. This includes development environments, debugging tools, static analysis systems, and various system utilities that handle COFF formatted files. Attackers can exploit this vulnerability remotely by delivering malicious COFF files through various attack vectors such as email attachments, web downloads, or compromised software repositories. The vulnerability is particularly concerning because it can be triggered without requiring special privileges or user interaction beyond opening the malicious file with a vulnerable application. This makes it a significant threat in environments where automated processing of binary files occurs, such as build systems, continuous integration pipelines, or security scanning tools that may inadvertently process compromised files.
Mitigation strategies for CVE-2017-17123 primarily involve upgrading to patched versions of GNU Binutils, specifically versions 2.30 or later where the vulnerability has been addressed through proper input validation and pointer checking. Organizations should also implement defensive measures such as validating all binary file inputs through multiple layers of security checks, including file format validation, size restrictions, and content analysis before processing with vulnerable libraries. Network-based protections can include implementing file type filtering and sandboxing mechanisms that prevent potentially malicious binary files from reaching systems that utilize the vulnerable BFD library. Additionally, system administrators should monitor for any applications that might be using older versions of Binutils and ensure comprehensive patching across all affected systems. This vulnerability demonstrates the importance of robust input validation in security-critical libraries and aligns with ATT&CK technique T1203, which covers exploitation of software vulnerabilities for privilege escalation and denial of service attacks. The remediation process should also include thorough testing of patched systems to ensure that the fix does not introduce regressions in legitimate file processing functionality while maintaining the security improvements necessary to prevent exploitation.