vulnerability / NVI-00003083 / Revision 2
Winter: ImportExportController AJAX handlers bypass granular import/export permission gate
GitHub lists this reviewed advisory for winter/wn-backend-module. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
8.3 high
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
winter/wn-backend-module
source listed<= 1.2.13
### Impact Affected versions of Winter CMS did not enforce the `ImportExportController` behavior's granular access control on the handlers that actually perform the work. The behavior supports per-operation access control through the `import[permissions]` and `export[permissions]` configuration keys, enforced by `userHasAccess()`. That check was applied only to the `import()` and `export()` page actions. `Backend\Classes\Controller::execAjaxHandlers()` dispatches AJAX handlers and returns *before* `execPageAction()` runs, and the behavior binds its import and export form widgets in its constructor on every request to the controller. The handlers were therefore fully functional without the gated page action ever executing, and none of them carried the check: - `onImport()` — reaches `$model->import()` with attacker-supplied column mappings - `onImportLoadForm()` - `onImportLoadColumnSampleForm()` - `onExport()` — reaches `$model->export()` - `onExportLoadForm()` - `download()` — streams a completed export file An authenticated backend user who could reach such a controller through its coarse `$requiredPermissions`, but who was denied the granular import or export permission, co
winter/wn-backend-module
source listedECOSYSTEM: introduced 0; fixed 1.2.14
### Impact Affected versions of Winter CMS did not enforce the `ImportExportController` behavior's granular access control on the handlers that actually perform the work. The behavior supports per-operation access control through the `import[permissions]` and `export[permissions]` configuration keys, enforced by `userHasAccess()`. That check was applied only to the `import()` and `export()` page actions. `Backend\Classes\Controller::execAjaxHandlers()` dispatches AJAX handlers and returns *before* `execPageAction()` runs, and the behavior binds its import and export form widgets in its constructor on every request to the controller. The handlers were therefore fully functional without the gated page action ever executing, and none of them carried the check: - `onImport()` — reaches `$model->import()` with attacker-supplied column mappings - `onImportLoadForm()` - `onImportLoadColumnSampleForm()` - `onExport()` — reaches `$model->export()` - `onExportLoadForm()` - `download()` — streams a completed export file An authenticated backend user who could reach such a controller through its coarse `$requiredPermissions`, but who was denied the granular import or export permission, co
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
- vendor patch
The original advisory lists fixed boundaries 1.2.14 for winter/wn-backend-module. Confirm the publisher’s latest guidance.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-fm29-4mq3-phg6 ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
- GHSA-fm29-4mq3-phg6 ↗
GitHub Advisory Database via OSV · vendor advisory
Observed . GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 2 ·
Source facts changed; compare the preserved prior revision.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.