CVE-2017-8421 in binutils
Summary
by MITRE
The function coff_set_alignment_hook in coffcode.h in Binary File Descriptor (BFD) library (aka libbfd), as distributed in GNU Binutils 2.28, has a memory leak vulnerability which can cause memory exhaustion in objdump via a crafted PE file. Additional validation in dump_relocs_in_section in objdump.c can resolve this.
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Analysis
by VulDB Data Team • 12/04/2024
The CVE-2017-8421 vulnerability resides within the Binary File Descriptor (BFD) library component of GNU Binutils version 2.28, specifically manifesting in the coff_set_alignment_hook function located in coffcode.h. This memory leak vulnerability represents a critical security flaw that can be exploited to cause memory exhaustion conditions within the objdump utility. The vulnerability stems from inadequate memory management during the processing of PE (Portable Executable) files, particularly when handling crafted malicious input that triggers the memory allocation sequence within the coff_set_alignment_hook function. The flaw enables an attacker to consume excessive system resources through carefully constructed PE files, potentially leading to denial of service conditions that affect the availability of the affected system.
The technical implementation of this vulnerability involves the improper handling of memory allocation within the BFD library's COFF (Common Object File Format) processing code. When objdump encounters a malformed PE file, the coff_set_alignment_hook function fails to properly release allocated memory resources, creating a memory leak that accumulates with each processed file. The dump_relocs_in_section function in objdump.c serves as the entry point where this vulnerability becomes exploitable, as it processes relocation information within sections and triggers the problematic memory allocation path. This memory leak pattern aligns with CWE-401, which specifically addresses improper release of memory after use, and represents a classic example of resource exhaustion vulnerabilities that can be leveraged to disrupt system operations.
The operational impact of CVE-2017-8421 extends beyond simple resource consumption, as it can be weaponized in various attack scenarios targeting systems that utilize objdump for binary analysis. Attackers can craft malicious PE files that, when processed by objdump, will cause progressive memory consumption until system resources are exhausted, resulting in denial of service conditions that prevent legitimate operations from completing successfully. This vulnerability is particularly concerning in environments where automated binary analysis tools are deployed, as it can be triggered through routine file processing activities. The impact affects systems running GNU Binutils 2.28 and potentially other versions that contain similar memory management flaws, making it a widespread concern across various software development and security analysis environments. The vulnerability's exploitation requires minimal privileges and can be executed through standard file processing workflows, making it an attractive target for attackers seeking to disrupt system availability.
Mitigation strategies for CVE-2017-8421 focus on implementing proper memory management practices within the BFD library and updating to patched versions of GNU Binutils. The recommended approach involves adding additional validation checks within the dump_relocs_in_section function to ensure proper memory cleanup occurs after processing relocation information in sections. Security practitioners should prioritize updating to GNU Binutils versions that contain the specific patch addressing this memory leak, which typically includes proper memory deallocation routines and enhanced input validation. System administrators should also consider implementing file validation controls that filter potentially malicious PE files before processing them through objdump, and monitor system resource consumption during binary analysis operations to detect potential exploitation attempts. The vulnerability's remediation aligns with ATT&CK technique T1499.004, which covers network denial of service, and represents a fundamental requirement for maintaining system availability in security analysis environments where resource management is critical for operational integrity.