CVE-2019-12818 : Security Advisory and Response

A vulnerability was found in the Linux kernel versions prior to 4.20.15. The issue lies in the nfc_llcp_build_tlv function, potentially leading to a denial of service due to a NULL pointer dereference.

Understanding CVE-2019-12818

This CVE identifies a vulnerability in the Linux kernel that can be exploited to cause a denial of service.

What is CVE-2019-12818?

This vulnerability is located in the nfc_llcp_build_tlv function within the Linux kernel, which may return NULL. Failure to verify this can result in a NULL pointer dereference, leading to a denial of service.

The Impact of CVE-2019-12818

The exploitation of this vulnerability can result in a denial of service, affecting the availability of the system.

Technical Details of CVE-2019-12818

This section provides more technical insights into the CVE.

Vulnerability Description

The nfc_llcp_build_tlv function in net/nfc/llcp_commands.c within the Linux kernel may return NULL. If not properly checked, this can trigger a NULL pointer dereference, causing a denial of service.

Affected Systems and Versions

Affected systems: Linux kernel versions prior to 4.20.15
Affected function: nfc_llcp_build_tlv in net/nfc/llcp_commands.c

Exploitation Mechanism

The vulnerability can be exploited through the nfc_llcp_build_gb function located in the file net/nfc/llcp_core.c.

Mitigation and Prevention

Protecting systems from CVE-2019-12818 is crucial to maintaining security.

Immediate Steps to Take

Update to Linux kernel version 4.20.15 or later to mitigate the vulnerability.
Regularly monitor security advisories and apply patches promptly.

Long-Term Security Practices

Implement secure coding practices to prevent NULL pointer dereference issues.
Conduct regular security audits and code reviews to identify and address vulnerabilities.

Patching and Updates

Stay informed about security updates and patches released by the Linux kernel community.
Apply patches promptly to ensure the security of the system.