Bypass validation by specifing same parameter multiple times

[ghost]

Describe the bug

If you specify a query-parameter multiple times, you can bypass the validation. Not tested for other locations

To Reproduce

1. Use simple validation as shown below
   app.get('/',[query("test").isAlphanumeric()], (req,res,next) => { validationResult(req).throw() //something })

2. http://localhost:8000/?test=A&test=!! --> passes

Expected behavior

Validation should fail, since express handles stuff like this as array.
Should check every value of given array.
--> { test: [ 'A', '!!' ] }

Current behavior

Validation passes

Express-validator version:

• Version: 6.12.0

[fedeci]

It is a known issue, it will be fixed in v7 (#1002).
For the moment if you expect test to be an array you should use wildcards like

query('test.*').isAlphanumeric()