CVE-2021-20681 Cross-site Scripting (XSS) in baserCMS
Remote authenticated attackers can inject arbitrary scripts into baserCMS page editing, potentially leading to code execution or account takeover.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-20681?
CVE-2021-20681 is a medium-severity cross-site scripting vulnerability in Basercms Basercms, published on 26 Mar 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Improper neutralization of JavaScript input in the page editing function of baserCMS versions prior to 4.4.5 allows remote authenticated attackers to inject an arbitrary script via unspecified vectors.
Weakness: CWE-79
Which versions are affected by CVE-2021-20681?
2 open source packages ship an affected version, including baserproject/basercms. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
baserproject/basercms Packagist | All versions | 4.4.5 |
baserproject/basercms Packagist | All versions | 4.4.5 |
Products include Basercms Basercms.
How do I fix CVE-2021-20681?
Upgrade baserproject/basercms to 4.4.5 or later.
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-2021-20681 being exploited?
There is no known exploitation of CVE-2021-20681 in the wild and no public exploit code.
Other vulnerabilities in Basercms Basercms
- CVE-2023-25654 baserCMS File Uploader Remote Code Execution (RCE) vulnerability
- CVE-2023-25655 baserCMS allows any file to be uploaded
- CVE-2017-10842 baserCMS SQL Injection vulnerability
- CVE-2026-30880 baserCMS: OS command injection vulnerability in installer
- CVE-2026-21861 baserCMS: OS Command Injection Leading to Remote Code Execution (RCE)
Sources
Also known as GHSA-24p5-x9f9-vvpx.