CVE-2021-32735 Cross-site scripting (XSS) from field and configuration text displayed in the Panel
Authenticated users or frontend visitors can inject scripts via page titles in the Kirby CMS Panel, potentially escalating privileges or hijacking admin sessions.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-32735?
CVE-2021-32735 is a high-severity cross-site scripting vulnerability in getkirby kirby, published on 2 Jul 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Kirby is a content management system. In Kirby CMS versions 3.5.5 and 3.5.6, the Panel's `ListItem` component (used in the pages and files section for example) displayed HTML in page titles as it is. This could be used for cross-site scripting (XSS) attacks. Malicious authenticated Panel users can escalate their privileges if they get access to the Panel session of an admin user. Visitors without Panel access can use the attack vector if the site allows changing site data from a frontend form. Kirby 3.5.7 patches the vulnerability. As a partial workaround, site administrators can protect against attacks from visitors without Panel access by validating or sanitizing provided data from the frontend form.
Which versions are affected by CVE-2021-32735?
2 open source packages ship an affected version, including getkirby/cms. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
getkirby/cms Packagist | All versions | 3.5.7 |
getkirby/cms Packagist | All versions | 3.5.7 |
Products include Getkirby Kirby.
How do I fix CVE-2021-32735?
Upgrade getkirby/cms to 3.5.7 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-2021-32735 being exploited?
There is no known exploitation of CVE-2021-32735 in the wild and no public exploit code.
Other vulnerabilities in getkirby kirby
- CVE-2024-26483 Kirby vulnerable to unrestricted file upload of user avatar images
- CVE-2024-41964 Insufficient permission checks in the language settings in Kirby CMS
- CVE-2026-34587 Kirby has Server-Side Template Injection (SSTI) via double template resolution in option rendering
- CVE-2021-29460 Cross-site scripting (XSS) from unsanitized uploaded SVG files
- CVE-2023-38489 Kirby vulnerable to Insufficient Session Expiration after a password change
Sources
Also known as GHSA-2f2w-349x-vrqm.