Fix timing attack on login form (opr #676) #39
Merged
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As detailed in #357 the time it takes to process a login request is
considerably less if the user specified doesn't exist than if the
password is incorrect. This can be used as a user enumeration attack,
even if the login error messages were customized to avoid this.
I fixed it by increasing the response time of a non-existing user
request by hashing the given password anyway (if using good
password hashing algorithm this is what takes a relatively
large amount of time and makes the attack possibly).
closes #357