CVE-2021-27910 Stored XSS vulnerability on Bounce Management Callback
Attackers can inject arbitrary JavaScript via unauthenticated webhook callbacks, leading to code execution and data theft when users view lead details.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-27910?
CVE-2021-27910 is a high-severity cross-site scripting vulnerability in Mautic, published on 30 Aug 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
Insufficient sanitization / filtering allows for arbitrary JavaScript Injection in Mautic using the bounce management callback function. The values submitted in the "error" and "error_related_to" parameters of the POST request of the bounce management callback will be permanently stored and executed once the details page of an affected lead is opened by a Mautic user. An attacker with access to the bounce management callback function (identified with the Mailjet webhook, but it is assumed this will work uniformly across all kinds of webhooks) can inject arbitrary JavaScript Code into the "error" and "error_related_to" parameters of the POST request (POST /mailer/<product / webhook>/callback). It is noted that there is no authentication needed to access this function. The JavaScript Code is stored permanently in the web application and executed every time an authenticated user views the details page of a single contact / lead in Mautic. This means, arbitrary code can be executed to, e.g., steal or tamper with information.
Weakness: CWE-79
Which versions are affected by CVE-2021-27910?
4 open source packages ship an affected version, including mautic/core. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mautic/core Packagist | All versions | 3.3.4 |
mautic/core Packagist | All versions | 3.3.4 |
mautic/core Packagist | From 4.0.0-alpha1 | 4.0.0 |
mautic/core Packagist | From 4.0.0-alpha1 | 4.0.0 |
Products include Acquia Mautic.
How do I fix CVE-2021-27910?
Upgrade mautic/core to a fixed version for your release line: 3.3.4 or 4.0.0.
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-2021-27910 being exploited?
There is no known exploitation of CVE-2021-27910 in the wild and no public exploit code.
Other vulnerabilities in Mautic
- CVE-2022-25772 Cross-site Scripting vulnerability in Mautic's tracking pixel functionality
- CVE-2020-35125 Mautic is vulnerable to XSS vulnerability
- CVE-2020-35124 XSS vulnerability leveraged through referrers could allow un-authorized admin access in Mautic
- CVE-2024-47051 Remote Code Execution & File Deletion in Asset Uploads
- CVE-2020-35128 Mautic stored Cross-site Scripting (XSS)
Sources
Also known as GHSA-86pv-95mj-7w5f.