Security: State-changing GET endpoint is marked NoCSRFRequired and can be abused for CSRF-driven storage spam#8212
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`getCalendarDotSvg` is documented as `@NoCSRFRequired` and performs a write operation (`newFile`) in app data based on request input. Because this is a GET-style retrieval endpoint with side effects, a third-party site can trigger authenticated users' browsers to hit it repeatedly, causing unwanted file creation and potential storage exhaustion/DoS. Signed-off-by: tomaioo <203048277+tomaioo@users.noreply.github.com>
tomaioo
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GVodyanov,
SebastianKrupinski and
tcitworld
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Summary
Security: State-changing GET endpoint is marked NoCSRFRequired and can be abused for CSRF-driven storage spam
Problem
Severity:
Medium| File:lib/Controller/ViewController.php:L70getCalendarDotSvgis documented as@NoCSRFRequiredand performs a write operation (newFile) in app data based on request input. Because this is a GET-style retrieval endpoint with side effects, a third-party site can trigger authenticated users' browsers to hit it repeatedly, causing unwanted file creation and potential storage exhaustion/DoS.Solution
Make the endpoint side-effect free (serve generated SVG directly without persisting), or require POST with CSRF protection for writes. Add rate limiting and cleanup/overwrite logic to prevent unbounded file growth.
Changes
lib/Controller/ViewController.php(modified)