CVE-2020-26238 : Security Advisory and Response

Cron-utils is a Java library used for parsing, validating, and migrating crons, along with providing human-readable descriptions. This CVE highlights a critical vulnerability present in versions prior to 9.1.3, allowing for template injection and potential unauthenticated Remote Code Execution (RCE) attacks.

Understanding CVE-2020-26238

This section delves into the specifics of the vulnerability and its impact.

What is CVE-2020-26238?

CVE-2020-26238 is a template Injection vulnerability in cron-utils versions before 9.1.3. It enables attackers to inject arbitrary Java EL expressions, leading to unauthenticated Remote Code Execution (RCE) vulnerabilities.

The Impact of CVE-2020-26238

The impact of this vulnerability is rated as high, with a CVSS base score of 7.9. It affects confidentiality, integrity, and requires low privileges for exploitation.

Technical Details of CVE-2020-26238

Explore the technical aspects of the CVE in this section.

Vulnerability Description

The vulnerability arises from improper neutralization of special elements in output used by a downstream component, allowing for injection attacks.

Affected Systems and Versions

Product: cron-utils
Vendor: jmrozanec
Versions Affected: < 9.1.3

Exploitation Mechanism

The vulnerability can be exploited by injecting Java EL expressions through the @Cron annotation, affecting projects using this feature.

Mitigation and Prevention

Learn how to mitigate and prevent the exploitation of this vulnerability.

Immediate Steps to Take

Upgrade cron-utils to version 9.1.3 or higher to patch the vulnerability.
Avoid using untrusted Cron expressions with the @Cron annotation.

Long-Term Security Practices

Regularly update libraries and dependencies to the latest secure versions.
Conduct security audits and code reviews to identify and address vulnerabilities.

Patching and Updates

Ensure timely application of security patches and updates to mitigate known vulnerabilities.