CVE-2021-41127 : Vulnerability Insights and Analysis

Rasa is an open-source machine learning framework for text and voice-based conversations. A vulnerability in versions prior to 2.8.10 allows a malicious actor to overwrite or replace bot files by manipulating a crafted model file.

Understanding CVE-2021-41127

In this CVE, a security flaw in Rasa versions before 2.8.10 enables an attacker to exploit how model files are loaded, leading to potential arbitrary file manipulations.

What is CVE-2021-41127?

The vulnerability arises from the improper validation of paths in model files, allowing an attacker to tamper with essential bot files.

The Impact of CVE-2021-41127

The vulnerability has a CVSS base score of 7.3 (High severity) and can result in a malicious actor gaining unauthorized access to critical system files and data.

Technical Details of CVE-2021-41127

This section explores the technical aspects and implications of the identified vulnerability.

Vulnerability Description

A flaw in the loading mechanism of model

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files allows for a maliciously crafted model file to be loaded, potentially leading to the overwriting or replacement of critical bot files.

Affected Systems and Versions

Vulnerable Versions: Prior to 2.8.10

Exploitation Mechanism

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: Required
Scope: Unchanged
Integrity Impact: High
Availability Impact: High
Confidentiality Impact: None
Exploitation can be carried out through crafted model files, exploiting the path traversal vulnerability.

Mitigation and Prevention

Protect your systems against CVE-2021-41127 by following these mitigation strategies:

Immediate Steps to Take

Update Rasa to version 2.8.10 or later to eliminate the vulnerability.
Avoid uploading untrusted model files to Rasa instances.
Restrict CLI and API endpoint access to prevent unauthorized intrusion.

Long-Term Security Practices

Conduct regular security assessments and audits on Rasa deployments.
Educate users on safe file-handling practices and potential risks of model file uploads.

Patching and Updates

Stay informed about security patches and updates released by RasaHQ to address vulnerabilities promptly.