CVE-2017-17053 : Security Advisory and Response

In the Linux kernel version earlier than 4.12.10, a vulnerability exists in the init_new_context function that can be exploited by a local attacker to achieve a use-after-free or cause unintended consequences by running a specially crafted program.

Understanding CVE-2017-17053

This CVE involves a flaw in the Linux kernel that mishandles errors during LDT table allocation when forking a new process, potentially leading to a use-after-free vulnerability.

What is CVE-2017-17053?

The vulnerability in the Linux kernel version prior to 4.12.10 allows a local attacker to exploit a use-after-free vulnerability or cause unintended consequences by executing a specially crafted program.

The Impact of CVE-2017-17053

The vulnerability enables a potential attacker within the system to exploit a use-after-free vulnerability or potentially cause other unintended consequences by executing a specifically crafted program.

Technical Details of CVE-2017-17053

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The init_new_context function in the Linux kernel before version 4.12.10 does not correctly handle errors from LDT table allocation when forking a new process, allowing a local attacker to achieve a use-after-free or possibly have other unspecified impacts by running a specially crafted program.

Affected Systems and Versions

Affected System: Linux kernel versions earlier than 4.12.10
Configuration Requirement: Vulnerability present in kernels with CONFIG_MODIFY_LDT_SYSCALL=y configuration

Exploitation Mechanism

The vulnerability can be exploited by a local attacker running a specially crafted program to trigger the use-after-free vulnerability.

Mitigation and Prevention

Protecting systems from CVE-2017-17053 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update to Linux kernel version 4.12.10 or later to mitigate the vulnerability
Disable CONFIG_MODIFY_LDT_SYSCALL=y configuration if not required

Long-Term Security Practices

Regularly update the Linux kernel to the latest stable version
Implement least privilege principles to limit the impact of potential vulnerabilities

Patching and Updates

Apply patches provided by the Linux kernel maintainers to address the vulnerability