CVE-2026-126663 · Package
NO FIX YET · SEE WHAT TO DO
Contao's {{image::}} insert tag accepts percent-encoded path traversal sequences such as ..%2f that bypass its path check, so a content editor can make the frontend resize and serve image files outside the files directory. An attacker with editor access can read any image file the web server can open.
first public Nov 11, 2026 · 1 source
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Sites running affected Contao versions where content editors have back-end access to insert content with the image insert tag. The flaw is in the frontend image resize path, so exposure depends on who can edit content. Sites on unaffected versions can skip it.
Not affected if no-untrusted-editors, unaffected-version
Who cares contao, php, self-hosted
composer show contao/core-bundle or composer show contao/manager-bundle{{image::}} insert tags in content use encoded ..%2f sequences5.3.54 or later5.7.17 or later6.0.6 or laterContao 4.0.0 before 5.3.54, 5.4.0 before 5.7.17, and 6.0.0 before 6.0.6 contains a path traversal vulnerability that allows content editors to read image files anywhere on the filesystem via the {{image::}} insert tag. Attackers can embed percent-encoded sequences like ..%2f that pass Validator::isInsecurePath() before rawurldecode(), making the frontend resize and serve readable image files outside the files directory.
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