Vulnerability Description
plone.app.textfield provides a zope.schema-style field type called RichText for storing a value with a related MIME type. Prior to 2.0.2, 3.0.2, and 4.0.1, depending on the release line, RichTextValue.output returns an unsanitized stored RichText value when mimeType equals outputMimeType, including values that claim the text/x-html-safe output type. This equality shortcut bypasses the safe_html transform even though the transform itself correctly removes event-handler attributes and unsafe URI schemes. Equal types can result from a RichText field configured with the same mimeType and outputMimeType or from REST API input that supplies text/x-html-safe as its content type. The raw stored value is then emitted through tal:content=structure without escaping, allowing a user who can set a RichText field to store JavaScript that executes in a viewer's browser. This issue is fixed in versions 2.0.2, 3.0.2, and 4.0.1.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/plone/plone.app.textfield/commit/0da1aeec2406cf640977eb857a03
- https://github.com/plone/plone.app.textfield/commit/467638e500d804c637031387a227
- https://github.com/plone/plone.app.textfield/commit/781d517a38524087fe57525a9480
- https://github.com/plone/plone.app.textfield/security/advisories/GHSA-4r4f-gg25-
FAQ
What is CVE-2026-54503?
CVE-2026-54503 is a vulnerability with a CVSS score of 4.3 (MEDIUM). plone.app.textfield provides a zope.schema-style field type called RichText for storing a value with a related MIME type. Prior to 2.0.2, 3.0.2, and 4.0.1, depending on the release line, RichTextValue...
How severe is CVE-2026-54503?
CVE-2026-54503 has been rated MEDIUM with a CVSS base score of 4.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-54503?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.