Strong Passwords: The Problem with Rotation
Published: 10 June 2021
Password rotation has previously been included within best practice guides as a method of minimising the risk of compromised passwords being valid at the time a threat actor attempts to use them. Recent research has indicated that the enforcing password rotation is linked to increased risk of weak passwords, due to users selecting passwords based on patterns - such as `Password1`, `Password2`, `Password3`, or patterns such as `Summer 2021`, `Autumn 2021`, `Winter 2021`.
Strong Passwords: The Problem with Complexity
Published: 07 June 2021
Weak passwords are those which are predictable and can be easily guessed. To ensure that users do not select weak passwords organisations may look to enforce password complexity. Complexity refers to the requirement to use a mixed character set. For example, on Active Directory accounts complexity requires three of the four: uppercase, lowercase, numbers, and symbols. However it is still possible to select weak passwords with complexity enabled, such as `Welcome!`, `Summer2020`, or `Password123456`.
Strong Passwords: Three Random Words
Published: 23 January 2021
When performing security tests, we very often come across weak passwords. We often see dictionary words with suffixes such as Welcome1, Password123, or Lockdown2020. We also see "leet" substitutions, such as P@55w0rd, 3l3ph@nt, or L0ckd0wn. We've previously shown how quickly password cracking can be performed. With passwords like the above they would be cracked easily. Simple protections such as "Password complexity" don't solve the problem on their own, for example complexity enforces the requirement for three of the following: uppercase, lowercase, numbers, and symbols - which all of the weak options above meet.
Preventing Windows Accounts Being Bruteforced
Published: 23 January 2021
In a previous article we discussed how bruteforcing Windows accounts is often easier than people expect. In this post - we'll cover some steps to harden these accounts.
The Observation Window
When configuring an account lockout threshold on a Domain another setting is suggested, the observation window. This setting effectively reduces the protection of the account lockout by setting a timer. For example, a lockout threshold of 5 and an observation window of 30 minutes has the impact of meaning that if an attacker attempts 5 incorrect passwords within 30 minutes the account will lock - but four passwords would not cause it to lock.
Therefore, an attacker could attempt 4 passwords every 30 minutes - or 192 per account per day, without locking any accounts.