Nextcloud · Report #840598
Possible denial of service when entering a loooong password
How it was found
You can create a very long password until you get the last user to put and aries or [DoS]. *Normally passwords have 8-10-24 digits. By sending a very long password (1.000.000 characters) Usually this problem is caused by a vulnerable password hashing implementation. When a long password is sent, the password hashing process will result in CPU and memory exhaustion.
**Remediation The password hashing implementation must be fixed to limit the maximum length of accepted passwords.
**step to reproduce:- 1.go to the link https://nextcloud.com/signup/ 2.try to signup there whatever email id you want then 3. on password field try to input many digits, hence you have generated it.
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Impact
it's possible to cause a denial a service attack on the server. This may lead to the website becoming unavailable or unresponsive.