Description
django CMS is an easy-to-use and developer-friendly enterprise content management system powered by Django. From 5.0.8 until 5.0.9, ContentRenderer.render_placeholder in cms/plugin_rendering.py can pass stored, attacker-controlled values to ContentRenderer.render_exception when plugin rendering fails in edit mode. Values from get_short_description(), the exception message, the placeholder, or placeholder.source are interpolated into a cms-rendering-exception heading and later returned through mark_safe. Because the heading is not escaped, stored HTML executes in an editor’s browser, and settings.DEBUG does not prevent the custom heading from rendering. The fix uses format_html to escape the message before safe placeholder output is returned. This issue is fixed in versions 5.0.9.
References4
Metrics
- CVSS 3.1
-
4.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 18 · as of 10 November 2026
- CWE
- CWE-79
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