CVE-2017-7549 : Exploit Details and Defense Strategies

An issue has been discovered in the instack-undercloud 7.2.0 package used in Red Hat OpenStack Platform Pike, the 6.1.0 package used in Red Hat OpenStack Platform Ocata, and the 5.3.0 package used in Red Hat OpenStack Newton. The vulnerability allows a local user to perform a symbolic-link attack, potentially leading to unauthorized file modifications.

Understanding CVE-2017-7549

This CVE identifies a security vulnerability in the instack-undercloud package versions for Red Hat OpenStack Platform Pike, Ocata, and Newton.

What is CVE-2017-7549?

The vulnerability in instack-undercloud versions Pike 7.2.0, Ocata 6.1.0, and Newton 5.3.0 allows local users to exploit insecure temporary files, enabling a symbolic-link attack to overwrite arbitrary file contents.

The Impact of CVE-2017-7549

The vulnerability could be exploited by a local user to perform a symbolic-link attack, thereby gaining the ability to overwrite the contents of any files they choose.

Technical Details of CVE-2017-7549

The technical details of the CVE-2017-7549 vulnerability are as follows:

Vulnerability Description

The issue arises from insecure temporary files used in pre-install and security policy scripts within the affected instack-undercloud packages.

Affected Systems and Versions

instack-undercloud 7.2.0 in Red Hat OpenStack Platform Pike
instack-undercloud 6.1.0 in Red Hat OpenStack Platform Ocata
instack-undercloud 5.3.0 in Red Hat OpenStack Newton

Exploitation Mechanism

The vulnerability allows a local user to exploit insecure temporary files, leading to a symbolic-link attack that enables the user to overwrite the contents of any files.

Mitigation and Prevention

To address CVE-2017-7549, consider the following mitigation strategies:

Immediate Steps to Take

Apply the patches provided by Red Hat for the affected versions.
Monitor system files for unauthorized modifications.

Long-Term Security Practices

Implement the principle of least privilege to restrict user access.
Regularly review and update security policies and scripts to prevent similar vulnerabilities.

Patching and Updates

Update the instack-undercloud package to the patched versions provided by Red Hat.