CVE-2026-42549
Flight has path traversal in `make:controller` CLI that creates arbitrary directories outside project root
Description
### Summary The `make:controller` CLI command calls `mkdir(..., recursive: true)` on a path built from the user-supplied controller name, **before** Nette's class-name validation runs. The class-file write is correctly rejected by Nette when the name contains `/`, but the recursive directory creation side effect is already committed — including directories located outside the project root through `../` traversal. ### Affected code `flight/commands/ControllerCommand.php` (≈ 63-66): ```php if (is_dir(dirname($controllerPath)) === false) { $io->info('Creating directory ' . dirname($controllerPath), true); mkdir(dirname($controllerPath), 0755, true); // un-normalized, runs before validation } ``` ### Proof of concept ``` $ php vendor/flightphp/runway/runway make:controller '../../../../tmp/CONTROLLER_TRAVERSAL_TEST/pwn' Creating directory .../app/controllers/../../../../tmp/CONTROLLER_TRAVERSAL_TEST Nette\InvalidArgumentException: Value '../../../../tmp/CONTROLLER_TRAVERSAL_TEST/pwnController' is not valid class name. $ ls /home/user/tmp/CONTROLLER_TRAVERSAL_TEST (directory exists — created before the exception was thrown) ``` ### Impact - **Arbitrary directory creation outside the project root**, executable by any local actor that can run the Flight CLI (developer machine, shared CI build agent, compromised dev container). - Primes log-file planting for chained LFI exploitation (e.g. creating a directory where an attacker can later drop a `.php` file to be included via a distinct template-include weakness). - On Windows, the `\` separator opens additional traversal surface. ### Patch (fixed in `3.18.1`, commit `b8dd23a`) The controller name is now normalized with `basename()` and validated against `^[A-Za-z_][A-Za-z0-9_]*$` before any `mkdir` side effect runs. ### Credit Discovered by **@Rootingg**.
How to fix CVE-2026-42549
To remediate CVE-2026-42549, upgrade the affected package to a fixed version below.
- —upgrade to 3.18.1 or later
Is CVE-2026-42549 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.