CVE-2019-9704 : Exploit Details and Defense Strategies

Vixie Cron before the 3.0pl1-133 Debian package allows local users to cause a denial of service (daemon crash) via a large crontab file because the calloc return value is not checked.

Understanding CVE-2019-9704

Vixie Cron vulnerability allowing local users to trigger a denial of service attack by crashing the daemon.

What is CVE-2019-9704?

This CVE refers to a vulnerability in Vixie Cron where local users could exploit the software to crash the daemon by providing a large crontab file.

The Impact of CVE-2019-9704

The vulnerability could be exploited by local users to cause a denial of service (DoS) attack by crashing the Vixie Cron daemon.

Technical Details of CVE-2019-9704

Vulnerability in Vixie Cron before the 3.0pl1-133 Debian package.

Vulnerability Description

The issue arises from the lack of proper checking of the return value of the calloc function, allowing local users to crash the daemon.

Affected Systems and Versions

Product: N/A
Vendor: N/A
Versions: N/A

Exploitation Mechanism

Local users could exploit the vulnerability by providing a large crontab file, triggering a denial of service by crashing the daemon.

Mitigation and Prevention

Steps to address and prevent exploitation of CVE-2019-9704.

Immediate Steps to Take

Apply patches or updates provided by the vendor promptly.
Monitor system logs for any unusual activity related to cron jobs.
Limit access to cron configuration files to authorized users only.

Long-Term Security Practices

Regularly update and patch software to address known vulnerabilities.
Implement the principle of least privilege to restrict user access.

Patching and Updates

Stay informed about security advisories and updates from the software vendor.
Regularly check for and apply patches to mitigate potential vulnerabilities.