CVE-2021-3824 Cross-site scripting in OpenVPN Access Server

What is CVE-2021-3824?

CVE-2021-3824 is a medium-severity cross-site scripting vulnerability in OpenVPN Access Server, published on 23 Sep 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

OpenVPN Access Server 2.9.0 through 2.9.4 allow remote attackers to inject arbitrary web script or HTML via the web login page URL.

Weakness: CWE-79, CWE-84

Which versions are affected by CVE-2021-3824?

It affects 1 product.

Products include Openvpn Openvpn Access Server.

How do I fix CVE-2021-3824?

No fix has been published for CVE-2021-3824 yet. Limit exposure of the affected software until one is available.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2021-3824 being exploited?

There is no known exploitation of CVE-2021-3824 in the wild and no public exploit code.

Other vulnerabilities in OpenVPN Access Server

• CVE-2020-8953 Auth bypass in n/a Critical 9.8
• CVE-2021-4234 Denial of service in OpenVPN Access Server High 7.5
• CVE-2022-33737 Information disclosure in OpenVPN Access Server High 7.5
• CVE-2022-33738 Weak cryptography in OpenVPN Access Server High 7.5
• CVE-2020-36382 Denial of service in OpenVPN Access Server High 7.5

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-hqrg-vp62-hmj7.