GHSA-8w54-22w9-3g8f
MEDIUMCross-site Scripting and Open Redirect in Products.CMFPlone
Blast Radius
products-cmfploneReal-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
Plone is vulnerable to reflected cross site scripting and open redirect when an attacker can get a compromised version of the image_view_fullscreen page in a cache, for example in Varnish. The technique is known as cache poisoning. Any later visitor can get redirected when clicking on a link on this page. Usually only anonymous users are affected, but this depends on your cache settings.
Patches
No patch is available for the Products.CMFPlone 4 series. Versions 5.0 and higher are not affected, but two other packages used by these versions are affected.
plone.app.contenttypes has the same problem in all versions, see advisory.
In Plone 5.0-5.2, the default Products.ATContentTypes version has the same problem. See advisory.
Plone 5.2.7 and 6.0.0a3 will be released today and will include these fixes.
For all unpatched versions of the three packages, you can use the following workaround.
Workaround
Make sure the image_view_fullscreen page is not stored in the cache. In Plone:
- Login as Manager and go to Site Setup.
- Go to the 'Caching' control panel. If this does not exist, or 'Enable caching' is not checked, you should normally not be vulnerable.
- Click on the tab 'Caching operations'.
- Under 'Legacy template mappings' locate the ruleset 'Content item view'.
- From the last column ('Templates') remove 'image_view_fullscreen'.
- Click on Save.
Reporter
This vulnerability was responsibly disclosed to the Plone Security Team by Gustav Hansen, F-Secure Consulting. Thank you!
For more information
If you have any questions or comments about this advisory, email us at [email protected] This is also the correct address to use when you want to report a possible vulnerability. See our security report policy.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | products-cmfplone | all versions | 5.0.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for products-cmfplone. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update products-cmfplone to 5.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-8w54-22w9-3g8f 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 pinpoints whether GHSA-8w54-22w9-3g8f is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-8w54-22w9-3g8f. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-8w54-22w9-3g8f in your dependencies?
O3 detects GHSA-8w54-22w9-3g8f across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.