CVE-2020-12049 : Exploit Details and Defense Strategies

CVE-2020-12049 is a vulnerability in dbus affecting versions before 1.12.18, leading to a file descriptor leak that could be exploited by a local attacker to deny service to subsequent D-Bus clients.

Understanding CVE-2020-12049

What is CVE-2020-12049?

The issue in dbus allows a local attacker to exhaust the file descriptor limit of a system service, potentially causing a denial of service for D-Bus clients.

The Impact of CVE-2020-12049

The vulnerability could be exploited by attackers with access to the D-Bus system bus or other system services' private AF_UNIX socket, leading to service denial for subsequent D-Bus clients.

Technical Details of CVE-2020-12049

Vulnerability Description

Discovered in dbus >= 1.3.0 before 1.12.18
DBusServer in libdbus leaks file descriptors when a message exceeds the per-message file descriptor limit

Affected Systems and Versions

Vendor: n/a
Product: n/a
Versions affected: n/a

Exploitation Mechanism

Local attacker with access to D-Bus system bus or private AF_UNIX socket
Exploits the file descriptor leak to exhaust the system service's file descriptor limit

Mitigation and Prevention

Immediate Steps to Take

Update dbus to version 1.12.18 or later
Monitor system services for unusual file descriptor activity

Long-Term Security Practices

Implement least privilege access controls
Regularly review and update system services and dependencies

Patching and Updates

Apply patches provided by dbus to address the file descriptor leak vulnerability