Hack your own MySQL to log in as root

$> sudo service mysql stop

$> mysqld --skip-grant-tables

$> mysql

mysql> FLUSH PRIVILEGES;

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'root';

mysql> SELECT host, user, plugin FROM mysql.user;

(source)

When Postgres allows any password

Problem: Postgres does not check my password, i.e. it accepts all passwords.

Solution: pg_hba.conf and change trust to md5. Restart postgres. That is all.

(source)

How to do authentication with Mojolicious

It's like this:

Non-functional checklist

When writing a user story or writing a spec for a piece of development work, consider the following non-functional aspects:

• Authentication
• Session management
• Access control
• Input validation
• Output encoding/escaping
• Encryption
• Error handling and logging
• Data protection
• Communication security
• HTTP security features
• Monitoring
• Logging of significant code paths
• Logging of expected events and errors
• Catching and logging of unexpected errors (crashes)
• Metrics for stats of usage and throughput (requests)
• Performance, e.g. response time must be <500ms

This is especially useful when building new systems like a new app or API.

SSH warning: authenticity of host can't be established

Problem

The authenticity of host 'example.com (1.2.3.4)' can't be established.
RSA key fingerprint is ab:cd:ef:12:34:56:78:90:ab:cd:ef:12:34:56:78:90
Are you sure you want to continue connecting (yes/no)?

Solution

ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no

Make sure you understand the security implications of doing this (Hint: they're not good).

(source)

Test Kerberos authentication

vi /etc/krb5.conf
/opt/mitk5/bin/kinit [username]