CVE-2026-54623 is a high-severity (CVSS 7.1) CWE-674 vulnerability in django-cms. A fix is available for django-cms — see the affected versions and patch details below.
django CMS: Plugin move endpoint allows cyclic reparenting (DoS)
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-54623.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-54623 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,386 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
django-cmsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Summary
The move_plugin admin endpoint does not prevent a plugin from being reparented under itself or one of its own descendants. Doing so creates a cycle in the plugin tree, after which the recursive descendant/ancestor SQL queries loop without terminating, stalling the request worker.
Details
move_plugin (in cms/admin/placeholderadmin.py) accepts a plugin_parent POST parameter and, for an in-placeholder move, sets the plugin's parent to the target without any cycle/ancestor check. If the target parent is a descendant of the moved plugin, the resulting parent_id graph contains a cycle.
Descendant and ancestor traversal is implemented with WITH RECURSIVE CTEs (_get_descendants_cte / _get_ancestors_cte in cms/models/pluginmodel.py) that have no cycle clause or depth limit. On a cyclic tree these recurse indefinitely (PostgreSQL/SQLite) or error at the recursion limit (MySQL). get_descendants() is invoked while building the move response and on subsequent operations on the affected subtree.
Impact
An authenticated staff user with permission to change plugins in at least one placeholder can corrupt that placeholder's plugin tree, causing requests that traverse it (rendering, copy, delete) to hang and consume application workers (denial of service). The tree is also left in a corrupted state.
Requires CMS_PERMISSION/plugin-change permission on a placeholder.
Patches
Fixed in 5.0.8: move_plugin now rejects (HTTP 400) any move that would place a plugin inside itself or one of its descendants, before any tree mutation or traversal.
Workarounds
None. Upgrade is recommended.
Credits
Reported by the security team at the University of Sydney ([@reporter]).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | django-cms | all versions | 5.0.8pip install --upgrade 'django-cms==5.0.8' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for django-cms, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update django-cms to 5.0.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-54623 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Frequently Asked Questions
Is CVE-2026-54623 in your dependencies?
Find it across PyPI, including transitive dependencies.