CVE-2020-5895 : What You Need to Know

NGINX Controller versions 3.1.0-3.3.0 are affected by a vulnerability that allows local system attackers to write arbitrary data into the socket, potentially leading to a denial of service (DoS) by causing AVRD segmentation fault (SIGSEGV).

Understanding CVE-2020-5895

This CVE identifies a security issue in NGINX Controller versions 3.1.0-3.3.0 that can be exploited by local attackers.

What is CVE-2020-5895?

The vulnerability in NGINX Controller versions 3.1.0-3.3.0 allows local system attackers to manipulate the socket, potentially causing a DoS by triggering AVRD segmentation fault.

The Impact of CVE-2020-5895

The vulnerability could lead to a DoS condition on the affected system, impacting its availability and potentially disrupting services.

Technical Details of CVE-2020-5895

NGINX Controller versions 3.1.0-3.3.0 are susceptible to a specific type of attack due to improper permissions on the AVRD socket.

Vulnerability Description

AVRD in NGINX Controller versions 3.1.0-3.3.0 uses world-readable and world-writable permissions on its socket, enabling local system attackers to write arbitrary data into the socket.

Affected Systems and Versions

Product: NGINX Controller
Vendor: n/a
Versions Affected: < 3.4.0

Exploitation Mechanism

Local system attackers can exploit the vulnerability by writing malformed messages to the socket, causing AVRD segmentation fault.

Mitigation and Prevention

It is crucial to take immediate steps to address and prevent the exploitation of CVE-2020-5895.

Immediate Steps to Take

Update NGINX Controller to version 3.4.0 or newer to mitigate the vulnerability.
Restrict access to the AVRD socket to authorized users only.

Long-Term Security Practices

Regularly monitor and audit permissions on critical system sockets.
Implement least privilege access controls to limit potential attack surfaces.

Patching and Updates

Apply security patches and updates provided by NGINX to address the vulnerability and enhance system security.