CVE intelligence and bounded remediation

CVE-2021-27909 — Acquia Mautic security vulnerability

Medium CVSS 6.3

For Mautic versions prior to 3.3.4/4.0.0, there is an XSS vulnerability on Mautic's password reset page where a vulnerable parameter, "bundle," in the URL could allow an attacker to execute Javascript code. The attacker would be required to convince or trick the target into clicking a password reset URL with the vulnerable parameter utilized.

Severity
Medium
CVSS
6.3 (3.1)
Published
2021-08-30
CISA KEV
Not currently listed
Ecosystem
javascript/npm
Weaknesses
CWE-79

Affected products

  • acquia / mautic
  • acquia / mautic / 4.0.0

Showing 2 representative product identities from 4 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Cross-site scripting and unsafe browser output

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace reflected, stored, and DOM-derived untrusted values into HTML, attributes, URLs, styles, scripts, and client-side template sinks.
  • Identify affected origins, authenticated user roles, sensitive browser capabilities, and where content is shared across tenants.
  • Review framework escaping, rich-text sanitization, legacy templates, and client-side rendering paths.

Remediate safely

  • Use context-aware framework output encoding and safe DOM APIs; keep untrusted data out of executable contexts.
  • Sanitize intentionally supported markup with a maintained allowlist policy and validate URLs and attributes separately.
  • Update affected rendering components and add tests for every output context using inert sentinel markup.

Authoritative sources

Complete CVE record and remediation plan

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