CVE-2021-41269 : Exploit Details and Defense Strategies

Cron-utils is a Java library used for defining, parsing, validating, migrating crons, and obtaining human-readable descriptions for them. The vulnerability allows for unauthenticated Remote Code Execution (RCE) due to a template injection in affected versions.

Understanding CVE-2021-41269

In this CVE, a critical vulnerability has been identified in cron-utils that can lead to unauthenticated RCE.

What is CVE-2021-41269?

The CVE-2021-41269 vulnerability in cron-utils enables attackers to inject arbitrary Java EL expressions, potentially resulting in unauthenticated RCE. Only projects using the @Cron annotation for untrusted Cron expressions are impacted.

The Impact of CVE-2021-41269

The impact of this CVE is rated as critical due to its potential for high availability, confidentiality, and integrity impacts, with a base score of 10.

Technical Details of CVE-2021-41269

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The vulnerability stems from a template injection in cron-utils, allowing for the injection of arbitrary Java EL expressions.

Affected Systems and Versions

Affected Product: cron-utils
Vendor: jmrozanec
Vulnerable Versions: < 9.1.6

Exploitation Mechanism

Attackers can exploit this vulnerability by injecting Java EL expressions via the @Cron annotation, enabling unauthenticated RCE.

Mitigation and Prevention

Protective measures to address and prevent exploitation of the vulnerability.

Immediate Steps to Take

Upgrade to version 9.1.6 to mitigate the vulnerability.

Long-Term Security Practices

Regularly update software to the latest versions.
Conduct code reviews to identify and address vulnerabilities.

Patching and Updates

Ensure regular patching of software components to address known vulnerabilities.