CVE-2017-17126 in binutils
Summary
by MITRE
The load_debug_section function in readelf.c in GNU Binutils 2.29.1 allows remote attackers to cause a denial of service (invalid memory access and application crash) or possibly have unspecified other impact via an ELF file that lacks section headers.
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Analysis
by VulDB Data Team • 01/17/2023
The vulnerability identified as CVE-2017-17126 resides within the GNU Binutils 2.29.1 suite, specifically in the readelf.c component which is responsible for examining and displaying information about ELF (Executable and Linkable Format) files. This flaw manifests in the load_debug_section function that processes debug sections within ELF binaries. The vulnerability represents a classic case of inadequate input validation where the function fails to properly handle ELF files that lack section headers entirely, creating a condition where the application encounters unexpected file structures during normal operation. Such deficiencies in input sanitization create exploitable conditions that can be leveraged by malicious actors to disrupt system operations.
The technical implementation of this vulnerability stems from the absence of proper bounds checking and validation within the load_debug_section function. When readelf encounters an ELF file without section headers, the function attempts to access memory locations that were never properly initialized or allocated, leading to invalid memory access patterns. This type of flaw falls under CWE-125, which describes out-of-bounds read conditions, and CWE-476, which addresses null pointer dereference scenarios. The function does not adequately verify the existence and validity of section header structures before attempting to process them, creating a path where arbitrary ELF files can trigger memory corruption. The vulnerability is particularly concerning because it operates at the binary analysis level where tools like readelf are commonly used for legitimate system administration and debugging purposes, making it an attractive target for attackers seeking to disrupt system availability.
The operational impact of CVE-2017-17126 extends beyond simple denial of service to potentially enable more sophisticated attack vectors. Remote attackers can craft malicious ELF files that, when processed by readelf, will cause the application to crash and terminate unexpectedly. This disruption of service can be particularly damaging in automated environments where readelf is invoked programmatically or in security analysis workflows where continuous operation is essential. The vulnerability's potential for unspecified other impacts suggests that under certain conditions, attackers might be able to achieve information disclosure or even arbitrary code execution, though this would require additional exploitation vectors. From an attack framework perspective, this vulnerability aligns with ATT&CK technique T1059.007 for execution through command and scripting interpreter, where malicious ELF files could be used to trigger the vulnerability in automated systems.
Mitigation strategies for CVE-2017-17126 primarily focus on immediate software updates and implementation of defensive programming practices. The most effective solution involves upgrading to GNU Binutils versions that contain patches addressing this specific vulnerability, which were released in subsequent versions following 2.29.1. Organizations should implement comprehensive patch management protocols to ensure all instances of readelf and related binutils components are updated across their infrastructure. Additionally, defensive programming techniques should be employed such as implementing comprehensive input validation routines, adding proper null checks before memory access operations, and incorporating bounds checking mechanisms within the load_debug_section function. System administrators should also consider implementing sandboxing or containerization strategies when processing untrusted ELF files, ensuring that potential crashes or memory corruption events are isolated from critical system components. Network security measures such as file validation at ingress points can help prevent malicious ELF files from reaching systems where readelf might be executed, while monitoring solutions can detect unusual patterns of readelf usage that might indicate exploitation attempts.