Improper validation of URLs ('Cross-site Scripting') in Wagtail rich text fields
Impact
When saving the contents of a rich text field in the admin interface, Wagtail does not apply server-side checks to ensure that link URLs use a valid protocol. A malicious user with access to the admin interface could thus craft a POST request to publish content with javascript: URLs containing arbitrary code. The vulnerability is not exploitable by an ordinary site visitor without access to the Wagtail admin.
Patches
Patched versions have been released as Wagtail 2.11.7 (for the LTS 2.11 branch) and Wagtail 2.12.4 (for the current 2.12 branch).
Workarounds
For sites that cannot easily upgrade to a current supported version, the vulnerability can be patched by adding the following code to a wagtail_hooks.py module in any installed app:
from draftjs_exporter.dom import DOM
from wagtail.admin.rich_text.converters.html_to_contentstate import ExternalLinkElementHandler, PageLinkElementHandler
from wagtail.core import hooks
from wagtail.core.whitelist import check_url
def link_entity(props):
id_ = props.get('id')
link_props = {}
if id_ is not None:
link_props['linktype'] = 'page'
link_props['id'] = id_
else:
link_props['href'] = check_url(props.get('url'))
return DOM.create_element('a', link_props, props['children'])
@hooks.register('register_rich_text_features', order=1)
def register_link(features):
features.register_converter_rule('contentstate', 'link', {
'from_database_format': {
'a[href]': ExternalLinkElementHandler('LINK'),
'a[linktype="page"]': PageLinkElementHandler('LINK'),
},
'to_database_format': {
'entity_decorators': {'LINK': link_entity}
}
})Acknowledgements
Many thanks to Kevin Breen for reporting this issue.
For more information
If you have any questions or comments about this advisory:
- Visit Wagtail's support channels
- Email us at security@wagtail.io (if you wish to send encrypted email, the public key ID is
0x6ba1e1a86e0f8ce8)
Software afectado
Haz clic en una tecnología para ver todas sus vulnerabilidades.
| Plataforma | Paquete | Versiones vulnerables | Corregida en |
|---|---|---|---|
| Python (PyPI) | wagtail | < 2.11.7, >= 2.12, < 2.12.4 | 2.11.7, 2.12.4 |
Referencias
- https://github.com/wagtail/wagtail/security/advisories/GHSA-wq5h-f9p5-q7fx
- https://pypi.org/project/wagtail/
- https://nvd.nist.gov/vuln/detail/CVE-2021-29434
- https://github.com/wagtail/wagtail/commit/5c7a60977cba478f6a35390ba98cffc2bd41c8a4
- https://github.com/wagtail/wagtail/commit/915f6ed2bd7d53154103cc4424a0f18695cdad6c
- https://github.com/pypa/advisory-database/tree/main/vulns/wagtail/PYSEC-2021-114.yaml
- https://github.com/wagtail/wagtail
- https://github.com/wagtail/wagtail/compare/v2.11.6...v2.11.7
- https://pypi.org/project/wagtail
- Vector CVSS
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:N- Debilidad (CWE)
CWE-79- Plataforma
- Python (PyPI)
- Paquete
wagtail- Publicada
- 19.04.2021
- Actualizado
- 11.10.2026 15:17
Fuentes y licencias
OSV / GitHub Advisory Database - PYSEC-2021-114 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-wq5h-f9p5-q7fx - CC BY 4.0
Historial de vulnerabilidades: wagtail
Todas las vulnerabilidades publicadas de este paquete (Python (PyPI)), de la más reciente a la más antigua. Muestra si es un fallo aislado o un paquete que hay que vigilar.
- Entradas en total
- 30
- Primera → última
- 04.2020 08.2026
- Sin corrección
- 0
- Explotada en ataques
- 0
Distribución por gravedad
- Alta 5
- Media 22
- Baja 3
Divulgaciones por año
- 2020: 3
- 2021: 2
- 2022: 1
- 2023: 3
- 2024: 3
- 2025: 0
- 2026: 18
-
Improper validation of URLs ('Cross-site Scripting') in Wagtail rich text fields esta entrada
Identifica las vulnerabilidades de tu aplicación
Con la integración de DockRay y el inventario de software activado, DockRay compara las versiones notificadas de los componentes con las vulnerabilidades conocidas y avisa de las coincidencias confirmadas. La cobertura depende de la tecnología compatible y de los avisos disponibles.