CVE-2016-9480 in libdwarf
Summary
by MITRE
libdwarf 2016-10-21 allows context-dependent attackers to obtain sensitive information or cause a denial of service by using the "malformed dwarf file" approach, related to a "Heap Buffer Over-read" issue affecting the dwarf_util.c component, aka DW201611-006.
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Analysis
by VulDB Data Team • 10/04/2022
The vulnerability identified as CVE-2016-9480 represents a critical heap buffer over-read flaw within the libdwarf library version dated 2016-10-21. This security issue manifests when processing malformed dwarf debug information files, creating a context-dependent attack vector that can lead to information disclosure or denial of service conditions. The flaw specifically impacts the dwarf_util.c component, which serves as a crucial utility module for handling dwarf debugging data structures within the library. The vulnerability's classification as context-dependent means that successful exploitation requires specific conditions related to the input data being processed, making it particularly challenging to exploit in automated attacks but still highly dangerous when properly orchestrated.
The technical implementation of this heap buffer over-read occurs when the libdwarf library processes malformed dwarf files that contain crafted data structures designed to trigger memory access violations. The dwarf_util.c module fails to properly validate buffer boundaries during parsing operations, allowing an attacker to craft a dwarf file that causes the library to read beyond allocated memory boundaries. This memory corruption can result in the exposure of sensitive data from adjacent memory locations, potentially including stack contents, heap metadata, or other confidential information. The issue stems from inadequate bounds checking mechanisms within the parsing logic, which does not adequately verify the size and structure of dwarf debugging information before attempting to access memory regions.
From an operational standpoint, this vulnerability presents significant risks to systems that utilize libdwarf for processing debug information, particularly in development environments, debugging tools, and software analysis frameworks. The denial of service aspect of this vulnerability can severely impact applications that depend on proper dwarf file processing, potentially causing system crashes or application instability when encountering maliciously crafted debug files. Information disclosure risks are equally concerning, as attackers may be able to extract sensitive memory contents that could include cryptographic keys, user credentials, or other confidential data. The vulnerability's impact extends across multiple software domains including compilers, debuggers, profiling tools, and security analysis frameworks that rely on libdwarf for processing debugging information.
The flaw aligns with CWE-125, which specifically addresses "Out-of-Bounds Read" vulnerabilities, and demonstrates the critical nature of proper input validation in security-sensitive code components. This vulnerability also relates to ATT&CK technique T1550.002, which involves the exploitation of software vulnerabilities to gain access to systems or data, highlighting the potential for attackers to leverage this flaw for unauthorized information access. Organizations utilizing libdwarf should implement immediate mitigations including updating to patched versions of the library, implementing input validation controls, and conducting security assessments of systems that process dwarf debug files. The vulnerability underscores the importance of maintaining up-to-date security libraries and implementing proper memory safety practices in software development, particularly for components that handle structured data parsing and validation.