CVE-2019-15795 : What You Need to Know

Python-apt uses MD5 for validation vulnerability

Understanding CVE-2019-15795

This CVE involves a vulnerability in Python-apt that allows a man-in-the-middle attack due to the use of MD5 for file validation.

What is CVE-2019-15795?

The MD5 sums of downloaded files are only verified by python-apt in specific functions until version 1.9.0ubuntu1, potentially enabling the installation of modified packages.

The Impact of CVE-2019-15795

CVSS Base Score: 4.7 (Medium)
Attack Vector: Network
Attack Complexity: High
User Interaction: Required
Scope: Changed
Confidentiality and Integrity Impact: Low
This vulnerability could lead to a man-in-the-middle attack, compromising the integrity of the downloaded packages.

Technical Details of CVE-2019-15795

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

Vulnerability Description

The vulnerability arises from python-apt's use of MD5 for file validation, allowing potential exploitation by malicious actors.

Affected Systems and Versions

The following versions of Python-apt are affected:

0.8.3ubuntu7.5
0.9.3.5ubuntu3+esm2
1.1.0~beta1ubuntu0.16.04.7
1.6.5ubuntu0.1
1.9.0ubuntu1.2

Exploitation Mechanism

The vulnerability enables attackers to conduct man-in-the-middle attacks, intercepting and modifying packages during the download process.

Mitigation and Prevention

Protecting systems from CVE-2019-15795 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update Python-apt to the patched versions: 1.9.0ubuntu1.2, 1.6.5ubuntu0.1, 1.1.0~beta1ubuntu0.16.04.7, 0.9.3.5ubuntu3+esm2, or 0.8.3ubuntu7.5.
Monitor for any suspicious activities related to package installations.

Long-Term Security Practices

Implement secure download protocols to prevent man-in-the-middle attacks.
Regularly update software and libraries to address known vulnerabilities.

Patching and Updates

Stay informed about security advisories and promptly apply patches released by Canonical.