The GHOST bug is a critical security vulnerability that affects the GNU C Library (glibc) in Linux systems. Discovered in 2015, it enables attackers to exploit a buffer overflow in the gethostbyname function, potentially allowing them to execute malicious code remotely. Consequently, systems running the affected glibc versions become susceptible to unauthorized access and control.


The phonetics of the keyword “GHOST Bug” can be represented as:GHOST: /ghi oʊst/ (or simply /ɡoʊst/)Bug: /bʌg/In the International Phonetic Alphabet (IPA):GHOST: [ɡ.h.oʊ.s.t]Bug: [b.ʌ.g]

Key Takeaways

  1. GHOST Bug is a high-impact vulnerability affecting the Linux glibc library, which can result in remote code execution by attackers.
  2. It affects numerous Linux systems, specifically those running on earlier versions of glibc library, making it crucial for users to update and patch their systems.
  3. Preventive measures like using proper input validation and implementing comprehensive security measures can help mitigate the GHOST Bug risks.


The GHOST Bug is an important technology term because it refers to a critical security vulnerability discovered in the Linux operating system’s GNU C Library (glibc). This vulnerability, assigned CVE-2015-0235, enables attackers to potentially execute malicious code remotely or gain control over a targeted system without any authentication.

Often affecting a wide range of applications and devices running on Linux, the GHOST Bug poses a major risk to the stability and security of countless systems.

Consequently, understanding the term’s significance helps emphasize the need for timely security patches, continuous system monitoring, and the adoption of robust vulnerability management practices in order to maintain the safety and integrity of digital infrastructure.


The GHOST Bug is a critical vulnerability that was discovered in the GNU C Library (glibc), which is an essential component of the Linux operating system. Its purpose is to allow attackers to remotely take control of a vulnerable system by exploiting a weakness in the glibc’s handling of the ‘gethostbyname’ and ‘gethostbyname2’ functions.

In simple terms, this bug makes it possible for cybercriminals to execute malicious code and compromise security on Linux-based systems that have not yet been patched to address this vulnerability. Discovered in 2015, the GHOST Bug is noteworthy for its potential to wreak havoc on unpatched systems, particularly those running web servers, email servers or any Linux-based devices connected to the internet.

By exploiting this vulnerability, attackers can potentially access private data, disrupt operations, or utilize compromised systems for launching further attacks. As a result, the GHOST Bug underscores the critical importance of continuous software updates and implementing security patches in a timely manner.

Through staying vigilant and adhering to best practices, system administrators and end-users alike can help minimize the risks posed by such vulnerabilities and maintain the integrity of their systems.

Examples of GHOST Bug

The GHOST Bug, or CVE-2015-0235, was a critical vulnerability discovered in 2015 within the GNU C Library (glibc), which is used widely across Linux-based operating systems. This vulnerability could be exploited to enable remote code execution, potentially allowing attackers to take control of a system. Here are three real-world examples related to this bug:

Exim Mail Server: Exim, the widely-used mail transfer agent on Linux systems, was found to be vulnerable to the GHOST Bug. A successful exploitation of this server software could have allowed an attacker to send a specially crafted email to a server running Exim, resulting in a potential compromise of the system.

WordPress Hosting Environments: WordPress website hosting environments that were set up on Linux-based servers with the affected versions of glibc were also at risk. A successful attack could have granted unauthorized access to the server, enabling a hacker to modify or delete files, steal sensitive information, or launch further attacks using the compromised system.

Internet of Things (IoT) Devices: Many IoT devices running Linux-based operating systems and using the affected glibc versions were also vulnerable to the GHOST Bug. This could have led to attackers compromising smart devices and utilizing them as a part of a botnet or for other nefarious purposes.


What is the GHOST Bug?

The GHOST Bug is a serious vulnerability discovered in the GNU C Library (glibc) that affects Linux systems. This vulnerability can allow remote attackers to execute arbitrary code and gain control of the affected system. It was assigned the CVE identifier CVE-2015-0235.

How does the GHOST Bug work?

GHOST, which stands for “GetHOSTbyname”, is a vulnerability within the glibc library which handles host name resolution functions. The bug exists in the function called ‘gethostbyname()’ and its variations. It enables a buffer overflow, allowing attackers to write arbitrary data in memory, potentially leading to remote code execution.

Which systems are affected by the GHOST Bug?

Linux systems using glibc version 2.2 to 2.17 are affected by the GHOST Bug. However, other systems that do not rely on glibc, such as BSD-based systems, are not vulnerable. It is essential to update your Linux system to a patched glibc version to mitigate the risk associated with this vulnerability.

How can I protect my system from the GHOST Bug?

To protect your system from the GHOST Bug, you should update your Linux system to a patched glibc version. Many Linux distributions have already released security updates addressing this vulnerability, so it is recommended to check for available security updates from your distribution’s package manager and install them immediately.

What are the potential risks associated with the GHOST Bug?

The GHOST Bug poses significant risks to affected systems, as attackers can exploit this vulnerability to gain unauthorized access and potentially execute arbitrary code. This could lead to the leakage of sensitive data, disruption of services, and unauthorized use of system resources. In severe cases, attackers may completely compromise the affected system, requiring a complete reinstallation of the operating system and applications.

Related Technology Terms

  • Heartbleed Vulnerability
  • Buffer Overflow
  • Software Patching
  • GNU C Library (glibc)
  • Secure Shell (SSH)

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