CVE-2020-35512 : Vulnerability Insights and Analysis

A use-after-free vulnerability was discovered in D-Bus Development branch, dbus-1.12.x stable branch, and dbus-1.10.x and older branches, potentially leading to crashes or other undefined behaviors.

Understanding CVE-2020-35512

This CVE involves a use-after-free flaw in multiple versions of D-Bus, affecting systems with multiple usernames sharing the same UID.

What is CVE-2020-35512?

The vulnerability exists in D-Bus Development branch, dbus-1.12.x stable branch, and dbus-1.10.x and older branches.
It occurs when policy rules reference multiple usernames with the same UID, causing D-Bus to free memory incorrectly.

The Impact of CVE-2020-35512

Exploitation of this vulnerability could result in system crashes or other unpredictable behaviors.

Technical Details of CVE-2020-35512

This section provides more in-depth technical information about the vulnerability.

Vulnerability Description

A use-after-free flaw in D-Bus versions <= 1.13.16, <= 1.12.18, and <= 1.10.30 allows for potential memory corruption.

Affected Systems and Versions

D-Bus Development branch <= 1.13.16
dbus-1.12.x stable branch <= 1.12.18
dbus-1.10.x and older branches <= 1.10.30

Exploitation Mechanism

The vulnerability is triggered when multiple usernames sharing the same UID are referenced in policy rules, leading to incorrect memory freeing.

Mitigation and Prevention

To address CVE-2020-35512, follow these mitigation strategies:

Immediate Steps to Take

Update D-Bus to the fixed versions: >= 1.13.18, >= 1.12.20, 1.10.32.
Monitor vendor security advisories for patches and updates.

Long-Term Security Practices

Implement least privilege access controls to limit potential impact.
Regularly review and update security policies and configurations.

Patching and Updates

Apply security patches promptly to mitigate the risk of exploitation.