CVE-2019-17056 Explained : Impact and Mitigation

The function llcp_sock_create in the file net/nfc/llcp_sock.c within the AF_NFC network module in the Linux kernel version up to 5.3.2 does not properly enforce the CAP_NET_RAW capability, allowing regular users to create raw sockets, leading to a vulnerability known as CID-3a359798b176.

Understanding CVE-2019-17056

This CVE involves a vulnerability in the Linux kernel that allows unprivileged users to create raw sockets.

What is CVE-2019-17056?

The vulnerability arises from the lack of enforcement of the CAP_NET_RAW capability in the Linux kernel, enabling regular users to create raw sockets.

The Impact of CVE-2019-17056

The vulnerability can be exploited by unprivileged users to create raw sockets, potentially leading to unauthorized network access and other security risks.

Technical Details of CVE-2019-17056

This section provides more technical insights into the CVE.

Vulnerability Description

The function llcp_sock_create in net/nfc/llcp_sock.c in the AF_NFC network module in the Linux kernel through version 5.3.2 does not enforce CAP_NET_RAW, allowing unprivileged users to create a raw socket.

Affected Systems and Versions

Linux kernel versions up to 5.3.2

Exploitation Mechanism

Unprivileged users can exploit the vulnerability to create raw sockets, potentially compromising system security.

Mitigation and Prevention

Protecting systems from CVE-2019-17056 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply relevant security patches provided by the Linux kernel maintainers.
Monitor network activity for any suspicious behavior.

Long-Term Security Practices

Regularly update the Linux kernel to the latest stable version.
Implement the principle of least privilege to restrict user capabilities.

Patching and Updates

Stay informed about security advisories and updates from Linux distributions and vendors to apply patches promptly.