CVE-2017-15939 : Exploit Details and Defense Strategies

The Binary File Descriptor (BFD) library, known as libbfd, has a vulnerability in the dwarf2.c file, affecting GNU Binutils 2.29. Attackers can exploit this flaw by providing a malicious ELF file, leading to a denial of service due to a NULL pointer dereference.

Understanding CVE-2017-15939

This CVE involves a vulnerability in the libbfd library within GNU Binutils 2.29, impacting the handling of NULL files in a table within the .debug_line file.

What is CVE-2017-15939?

The vulnerability in the dwarf2.c file of the libbfd library allows remote attackers to trigger a denial of service by causing an application crash through a crafted ELF file.

The Impact of CVE-2017-15939

Attackers can exploit this vulnerability remotely by supplying a malicious ELF file, leading to a denial of service where the application crashes due to a NULL pointer dereference.
This vulnerability is related to the concat_filename function and is a result of an incomplete fix for CVE-2017-15023.

Technical Details of CVE-2017-15939

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

The issue in the dwarf2.c file of the libbfd library mishandles NULL files in a .debug_line file table, allowing attackers to cause a denial of service through a crafted ELF file.

Affected Systems and Versions

Product: Not applicable
Vendor: Not applicable
Versions: GNU Binutils 2.29

Exploitation Mechanism

Attackers can exploit this vulnerability remotely by providing a specially crafted ELF file to trigger a denial of service.

Mitigation and Prevention

To address and prevent the exploitation of CVE-2017-15939, follow these steps:

Immediate Steps to Take

Apply vendor patches and updates promptly.
Monitor security advisories for any new information or patches related to this vulnerability.

Long-Term Security Practices

Regularly update and patch software to mitigate known vulnerabilities.
Implement network security measures to prevent unauthorized access to vulnerable systems.

Patching and Updates

Ensure that Binutils 2.29 is updated with the latest patches to address this vulnerability.