CVE-2021-32805 : What You Need to Know

Flask-AppBuilder is an application development framework built on top of Flask. In affected versions, an open redirect vulnerability exists when using Flask-AppBuilder OAuth, allowing an attacker to craft a URL that redirects users to a malicious site. Upgrading to Flask-AppBuilder 3.2.2 or above can resolve this issue.

Understanding CVE-2021-32805

This CVE highlights a security vulnerability in Flask-AppBuilder that could be exploited to redirect users to untrusted sites.

What is CVE-2021-32805?

Flask-AppBuilder, when using OAuth, is susceptible to an open redirect vulnerability. Attackers can exploit this by sharing a carefully crafted URL with a trusted domain, leading users to malicious sites.

The Impact of CVE-2021-32805

The impact of this vulnerability is rated as HIGH with a CVSS base score of 7.2. It could result in users being redirected to harmful websites, compromising the integrity and confidentiality of data.

Technical Details of CVE-2021-32805

Flask-AppBuilder versions below 3.3.2 are affected by this vulnerability.

Vulnerability Description

The vulnerability allows attackers to create URLs that redirect users to a different, potentially malicious, site.

Affected Systems and Versions

Flask-AppBuilder versions less than 3.3.2 are impacted by this security flaw.

Exploitation Mechanism

Attackers can exploit this vulnerability by tricking users into clicking on a crafted URL that redirects to an untrusted site.

Mitigation and Prevention

If upgrading to Flask-AppBuilder 3.2.2 or higher is not feasible, users can take immediate steps and adopt long-term security practices to mitigate the risk.

Immediate Steps to Take

Users should filter HTTP traffic containing

?next={next-site}

where the

next-site

domain differs from the application to prevent redirection to malicious sites.

Long-Term Security Practices

Regular security assessments, code reviews, and user training on identifying suspicious URLs can enhance security posture.

Patching and Updates

Ensure timely patching of Flask-AppBuilder to versions 3.3.2 or newer to eliminate this vulnerability.