Wagtail, an open‑source CMS built on Django, contained a missing permission check on its preview endpoints. A user who can log in to the Wagtail admin area and knows a model's field names can submit a crafted form to request a preview rendering of any page, snippet, or site‑setting object that has previewing enabled. The rendered preview uses whatever data the attacker supplies, and because the template may reference other database fields, the response can leak content that normally requires edit rights. The vulnerability does not expose the object's existing data, but it can reveal other protected data. An unauthenticated visitor cannot trigger the flaw.

Vulnerable versions are all releases of Wagtail before 6.3.6, 7.0.4, 7.1.3, 7.2.2, and 7.3. These are the versions for the 6.x and 7.x major lines. The issue has been fixed in the releases listed above. The affected product is the Wagtail CMS distributed by Torchbox.

CVSS score 5.1 indicates medium severity. EPSS score below 1% suggests low probability of exploitation observed at the time of analysis, and the vulnerability is not yet in CISA's Known Exploited Vulnerabilities catalog. Exploitation requires administrative access to Wagtail and knowledge of model structure, so the attack surface is limited to authenticated insiders or attackers who have compromised an admin account. If used, the flaw could allow an attacker to render arbitrary data in page previews and potentially reveal sensitive information that would otherwise be protected by edit permissions.