CVE-2023-36814 is a high-severity (CVSS 7.5) CWE-770 vulnerability in products-cmfcore. A fix is available for products-cmfcore — see the affected versions and patch details below.
zopefoundation's Products.CMFCore vulnerable to unauthenticated denial of service and crash via unchecked use of input with Python's marshal module
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- 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-2023-36814.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-36814 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
products-cmfcore🐍products-cmfcoreReal-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
Impact
The use of Python's marshal module to handle unchecked input in a public method on PortalFolder objects can lead to an unauthenticated denial of service and crash situation. The code in question is exposed by all portal software built on top of Products.CMFCore, such as Plone. All deployments are vulnerable.
Patches
The code has been fixed in Products.CMFCore version 3.2.
Workarounds
Users can make the affected decodeFolderFilter method unreachable by editing the PortalFolder.py module in Products.CMFCore by hand and then restarting Zope. Go to line 233 of PortalFolder.py and remove both the @security.public decorator for decodeFolderFilter as well as the method's entire docstring. This is safe because the method is not actually used by current code.
References
- Products.CMFCore security advisory GHSA-4hpj-8rhv-9x87
Credits
Thanks go to Nicolas VERDIER from onepoint.
For more information
If you have any questions or comments about this advisory:
- Open an issue in the Products.CMFCore issue tracker
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | products-cmfcore | ≥ 3.0&&< 3.2 | 3.2pip install --upgrade 'products-cmfcore==3.2' |
| 🐍PyPI | products-cmfcore | all versions | 2.7.1pip install --upgrade 'products-cmfcore==2.7.1' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for products-cmfcore, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update products-cmfcore to 3.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-36814 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-36814 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-36814. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-36814 in your dependencies?
O3 Security finds CVE-2023-36814 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.