CVE-2017-14930 in binutils
Summary
by MITRE
Memory leak in decode_line_info in dwarf2.c in the Binary File Descriptor (BFD) library (aka libbfd), as distributed in GNU Binutils 2.29, allows remote attackers to cause a denial of service (memory consumption) via a crafted ELF file.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 06/06/2020
The vulnerability identified as CVE-2017-14930 represents a critical memory management flaw within the Binary File Descriptor library component of GNU Binutils 2.29. This issue specifically affects the dwarf2.c file's decode_line_info function, which is responsible for processing debugging information within ELF binary files. The flaw manifests as a memory leak that occurs when the BFD library attempts to parse malformed or crafted ELF files containing specially constructed debugging data. This vulnerability falls under the CWE-401 category of insufficient resource management, specifically focusing on memory resource exhaustion. The attack vector involves remote exploitation through the processing of maliciously crafted ELF files, making it particularly dangerous for systems that handle untrusted binary content.
The technical implementation of this vulnerability stems from improper memory deallocation within the decode_line_info function when processing malformed DWARF debugging information. When the BFD library encounters a crafted ELF file with corrupted or specially constructed line number information, the memory allocation for processing this data does not get properly released, leading to progressive memory consumption. This memory leak occurs during the parsing of debug line information sections within the ELF file structure, where the library fails to account for all allocated memory blocks during error conditions or malformed input processing. The vulnerability is particularly insidious because it can be triggered by simply opening or processing an ELF file, without requiring any special privileges or complex attack scenarios.
The operational impact of CVE-2017-14930 extends beyond simple denial of service, as it can be exploited to exhaust system resources and potentially cause system instability or crashes. Remote attackers can craft ELF files designed to trigger this memory leak, leading to progressive memory consumption that can eventually exhaust available system resources. This vulnerability directly maps to the ATT&CK technique T1499.004 for resource exhaustion attacks, where adversaries consume system resources to prevent legitimate use of services. The flaw affects any system running GNU Binutils 2.29 that processes ELF files, including development environments, build servers, and security scanning systems that may encounter untrusted binary content. The memory leak can compound over time, making systems increasingly vulnerable to system crashes or performance degradation, particularly in environments where automated processing of binary files occurs frequently.
Mitigation strategies for this vulnerability require immediate patching of affected GNU Binutils installations to version 2.30 or later, which contains the necessary fixes for the memory leak in the dwarf2.c file. Organizations should implement strict file validation procedures for ELF files, particularly those from untrusted sources, and consider implementing sandboxing or virtualization techniques when processing potentially malicious binary content. System administrators should monitor memory usage patterns for processes that utilize BFD library functions and implement automated alerts for unusual memory consumption. The fix addresses the root cause by ensuring proper memory deallocation in error handling paths and includes additional validation checks for debugging information sections within ELF files. Security teams should also consider implementing network-based filtering to prevent the transmission of suspicious ELF files and establish incident response procedures for memory exhaustion attacks targeting binary processing systems.