CVE-2023-3899 : Exploit Details and Defense Strategies

A local privilege escalation vulnerability was discovered in subscription-manager, specifically due to inadequate authorization of the com.redhat.rhsm1 D-Bus interface. This vulnerability could allow a low-privileged local user to modify configuration settings, potentially leading to a local privilege escalation to an unconfined root user.

Understanding CVE-2023-3899

This section provides insights into the nature of the CVE-2023-3899 vulnerability, its impacts, technical details, and mitigation strategies.

What is CVE-2023-3899?

The CVE-2023-3899 vulnerability in subscription-manager involves a flaw in the D-Bus interface com.redhat.RHSM1, which exposes methods that could be abused by local users to alter the registration state, change entitlements, and escalate privileges by tampering with configuration files.

The Impact of CVE-2023-3899

The impact of CVE-2023-3899 is rated as high, with the potential for local privilege escalation to compromise system integrity, confidentiality, and availability. Attackers could exploit this vulnerability to gain unauthorized access and perform malicious actions on affected systems.

Technical Details of CVE-2023-3899

This section delves into the technical aspects of the CVE-2023-3899 vulnerability, including a description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

The vulnerability arises from inadequate authorization of the com.redhat.RHSM1 D-Bus interface, enabling local users to manipulate system registration states by changing configuration parameters, potentially leading to privilege escalation.

Affected Systems and Versions

Subscription-manager versions 1.28.36 and later, including various Red Hat Enterprise Linux versions, are affected by this vulnerability. Specific version details can be found in the vulnerability report.

Exploitation Mechanism

By utilizing the com.redhat.RHSM1.Config.SetAll() method, low-privileged local users can exploit this vulnerability to tamper with system registration states, escalate privileges, and execute unauthorized configuration changes.

Mitigation and Prevention

To safeguard systems from CVE-2023-3899, immediate actions and long-term security practices are crucial.

Immediate Steps to Take

A workaround for mitigating CVE-2023-3899 involves masking the rhsm.service to prevent unauthorized D-Bus calls triggering the service. By masking the service, potential exploitation attempts can be thwarted temporarily.

Long-Term Security Practices

Implementing robust user authorization controls, monitoring D-Bus interface access, and regularly updating software versions to patch known vulnerabilities are essential long-term security measures to prevent similar privilege escalation risks.

Patching and Updates

Users are advised to apply relevant security updates and patches provided by the vendor to address the CVE-2023-3899 vulnerability effectively. Regularly monitoring for security advisories and promptly applying patches is crucial for maintaining system security.

By following these mitigation strategies and best practices, organizations can enhance the security posture of their systems and mitigate the risks associated with CVE-2023-3899.