Vulnerability · Published Aug 30, 2021 · Assigned by Mautic

CVE-2021-27910Stored XSS vulnerability on Bounce Management Callback

High 8.2

In plain English

A high-severity cross-site scripting in Mautic from Mautic. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.2High
Exploit odds (30 days)0.7%top 46.7% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Packagistmautic/core3.3.4GHSA-86pv-95mj-7w5f
Packagistmautic/core4.0.0GHSA-86pv-95mj-7w5f

Affected products (as reported)

VendorProductVersions
Mautic Mautic unspecified – before 3.3.4unspecified – before 4.0.0

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:N

References