CVE-2021-40893 : Security Advisory and Response

A Regular Expression Denial of Service (ReDOS) vulnerability discovered in validate-data v0.1.1 when validating crafted invalid emails.

Understanding CVE-2021-40893

This CVE-2021-40893 involves a ReDOS issue in the validate-data v0.1.1 library.

What is CVE-2021-40893?

A ReDOS vulnerability in validate-data v0.1.1 affecting the validation of crafted invalid emails.

The Impact of CVE-2021-40893

Attackers can exploit this vulnerability to cause denial of service by sending specially crafted emails, impacting the availability of the system.

Technical Details of CVE-2021-40893

This section dives into the technical aspects of the vulnerability.

Vulnerability Description

ReDOS vulnerability found in validate-data v0.1.1 during the validation of specific malicious email inputs.

Affected Systems and Versions

Affected version: v0.1.1 of validate-data.
All systems using this specific version are vulnerable to ReDOS attacks.

Exploitation Mechanism

Attackers trigger the ReDOS vulnerability in validate-data v0.1.1 by submitting carefully crafted malicious input strings that exploit the inefficiency of the regular expression engine.

Mitigation and Prevention

Steps to address and prevent exploitation of the CVE-2021-40893 vulnerability.

Immediate Steps to Take

Update the validate-data library to a patched version that fixes the ReDOS vulnerability.
Consider input validation to sanitize user-provided data and prevent malicious inputs.

Long-Term Security Practices

Regularly update dependencies and libraries to mitigate known vulnerabilities.
Implement rate-limiting mechanisms to prevent abuse of validation processes.

Patching and Updates

Stay informed about security advisories and patches released by the library maintainers to address ReDOS vulnerabilities.