CVE-2023-49090 : What You Need to Know

CarrierWave has a content-type allowlist bypass vulnerability, possibly leading to XSS.

Understanding CVE-2023-49090

CarrierWave, a file upload solution for Ruby web frameworks, has a security vulnerability that allows attackers to bypass the Content-Type allowlist, potentially resulting in cross-site scripting (XSS) attacks.

What is CVE-2023-49090?

CarrierWave's

allowlisted_content_type?

validation method is vulnerable to a Content-Type allowlist bypass. Attackers can exploit this by passing crafted values to the

content_type

argument, allowing unauthorized Content-Types not included in the

content_type_allowlist

.

The Impact of CVE-2023-49090

This vulnerability can lead to XSS attacks, where malicious scripts are injected into web pages viewed by other users. It poses a medium severity risk with high confidentiality impact.

Technical Details of CVE-2023-49090

The vulnerability has been assigned a CVSS base score of 6.8, indicating a medium severity issue. The attack complexity is low, with low privileges required and user interaction.

Vulnerability Description

The allowlist bypass vulnerability in CarrierWave's

allowlisted_content_type?

method allows unauthorized Content-Type values to be accepted, potentially leading to XSS attacks.

Affected Systems and Versions

Vendor: carrierwaveuploader
Product: carrierwave
Affected Versions: >= 2.2.0, < 2.2.5 and >= 3.0.0, < 3.0.5

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting values for the

content_type

argument to bypass the Content-Type allowlist, enabling the execution of malicious scripts.

Mitigation and Prevention

It is crucial to take immediate steps to address and prevent the exploitation of CVE-2023-49090.

Immediate Steps to Take

Update CarrierWave to the patched versions 2.2.5 and 3.0.5 to mitigate the vulnerability.
Review and restrict access to content-type validations to prevent unauthorized bypass.

Long-Term Security Practices

Regularly update software and libraries to patch known vulnerabilities.
Implement strict input validation and sanitization practices to prevent input-based attacks.

Patching and Updates

Stay informed about security advisories and updates from CarrierWave to address new vulnerabilities and apply patches promptly.