Password Spraying Attack: What You Need to Know and How to Prevent It

Password spraying has become a quiet crisis for modern organizations. Attackers no longer need complex tools; they just need one weak password in a sea of users. 

They move slowly, test common passwords across accounts and slip in without raising alarms. 

True protection starts when leadership sees identity as a real business risk and not just an IT issue.  This blog helps you build that awareness by showing how password spraying actually happens and why it slips past everyday controls. 

It highlights the signs that matter and the habits that create hidden risks. By the end you know what to strengthen and how to keep your organisation safer.

What Is a Password Spraying Attack?

A password spraying attack is when one common password is tried across many accounts. It moves slow so the system does not trigger lockouts. You do not see repeated failed attempts on a single user. You only see one attempt spread across the whole environment.

• Attack Method. The attacker chooses a small list of common passwords like season-year patterns or welcome-type passwords. They use each password once across many accounts.
• Why It Works. Many users reuse simple or predictable passwords because they are easy to remember. Even with password policies in place these patterns continue. The attacker only needs one user to slip.
• Common Targets. Email portals, cloud identity systems, VPN gateways and public login pages are primary targets because they are accessible from the internet. Accounts without MFA are the easiest to take. Legacy authentication also opens the door.  Understanding password spray attacks helps you spot where to focus defenses.

How Password Spraying Works

• Step 1. Build the target list. The attacker creates a clean list of real user accounts by collecting names from sources and testing patterns until only valid identities remain. This list becomes the foundation of the campaign and shapes every action that follows in the attack.‍
• Step 2. Prepare the password set. The attacker builds a short list of passwords that people often reuse and trusts that one choice will open a single account. This list guides the pace of the attack and becomes the tool that drives each quiet attempt effectively.‍
• Step 3. Start the low and slow attempts. The attacker begins low and slow attempts that spread login activity over long periods so nothing triggers alerts and every move looks normal. Each try uses one password on many accounts and the slow rhythm helps the attacker avoid suspicion.‍
• Step 4. Blend into normal traffic. The attacker hides inside normal traffic by rotating IP sources, adjusting timing to match user hours and pausing after any progress so activity blends into daily patterns. Once a password works the attacker searches the account for access paths inside.

Password Spraying vs. Brute Force: Key Differences

Both methods try to gain access by guessing passwords but their style and pace are completely different. Brute force pushes fast and loud. Password spraying moves slowly and quietly. One tries many passwords on one account. The other tries one common password across many accounts.

• Attempt Pattern. Brute force hits a single account with many password guesses. Password spraying uses one password across many accounts. The spraying method spreads risk and avoids lockouts.
• Speed and Timing. Speed and Timing. Brute force works at high speed and wants quick results. Password spraying works over long time spans and waits between attempts so systems do not notice. In cyber security this attack demands long window monitoring rather than short burst alerts.
• Detection Risk. Brute force triggers lockouts and alarms quickly. Password spraying hides inside normal login patterns which makes detection harder. Good practice pairs detection with policy so you can move from spotting to password spraying attack prevention.
• Success Strategy. Brute force depends on computing power to break a password. Password spraying depends on user habits and weak password choices. Spraying succeeds when even one person uses a predictable password.

How to Detect a Password Spraying Attack

Spotting a password spraying attack is not about a big obvious warning. It shows up in quiet little patterns because the attacker moves slowly on purpose. Real detection comes from noticing those subtle repeats before they stack into trouble.

• Failed Login Clustering. When many users show failed attempts using the same password that is not normal. Check if these attempts hit in small waves across different accounts. If several accounts report the same failure pattern it suggests someone is testing one password across the group.
• Unusual Source Patterns. Watch where sign in attempts are coming from. If you notice repeated tries from cloud hosting platforms or IPs that shift location often that deserves attention. Also watch for logins that happen at odd times for your team.
• Account Anomalies. After one account opens attackers usually start making quiet tweaks. Look for new mail forwarding rules, new connected apps or unexplained password resets. These small adjustments help the attacker stay inside without needing to log in again.
• Correlation and Hunting. Connect signals from different systems. Failed logins device changes new IP patterns and user complaints often tell one combined story. Once you confirm the activity, move fast to contain the impact and apply the steps that strengthen your network against this type of attack.

How Password Spraying Can Harm Your Business

A single successful password spraying attack can open a quiet door into your systems. This is a classic password spraying example. Attackers move slowly and look for the easiest paths into mail and shared drives. One weak password can become a chain that lasts weeks and months.

• Unauthorized Access to Internal Systems. A compromised account gives an attacker a real view of how your business works and the risk is larger than most teams expect. The ASD report shows that 60 percent of notifiable breaches involved compromised credentials. 
• Data Theft and Leakage. Attackers copy sensitive files from drives and mailboxes. They can send data out or sell it to others. Leaked customer records or financial reports cause regulatory headaches and damage relationships. 
• Privilege Escalation and Lateral Movement. From one account attackers search for admin tools and shared credentials and they quietly move deeper through the environment. 
• Business Disruption and Financial Impact.  A compromise forces emergency response and system lockdowns and daily work stops until the damage is understood. A Howden survey reported by Reuters shows British businesses lost about USD 55 billion to cyberattacks in five years. 

Real-World Examples of Password Spraying Attacks

Password spraying shows up today because attackers know at least one weak password usually exists somewhere. The attack moves slowly. Login attempts spread across many accounts so everything looks normal.

• Microsoft 365 Tenant Compromise. In 2024 Microsoft highlighted that password attacks across Microsoft 365 now happen at over 4000 attempts every second. In one case an attacker entered through a mailbox with a simple password.
• Financial Fraud. In 2019 the City of London Corporation responsible for governing the financial district was hit by a password-spraying attack aimed at its email systems and the goal was to gain unauthorized access to email accounts and sensitive information.

How to Respond to a Password Spraying Attack

Response works best when you stay calm and move with clear steps. The goal is to stop access, close the entry points and check how far the attacker went. The situation may look small at first but treat it seriously. One opened account can connect to many parts of your system.

• Freeze the Impact Quickly. Start by forcing password resets for the accounts involved. Turn on MFA if it is not active. Remove suspicious mail forwarding rules and strange app permissions.
• Check Activity Trails. Look at login times device types and sign in locations for the affected accounts. See if the attacker viewed internal files or tried to access admin areas. Pay extra attention to accounts that handle financial tools or shared drives.
• Remove Hidden Persistence. Attackers often leave quiet backdoors. Look for new connected apps, new mailbox rules and unfamiliar access tokens. Remove them one by one. Confirm that no new accounts were created during the breach.
• Strengthen the Weak Spots. Identify where the weak password came from. Educate teams on strong passphrases. Require MFA across critical systems. Review lockout and login monitoring rules so slow attempts show up earlier next time. 

How to Defend and Mitigate Password Spraying Attacks

The goal here is simple. Close the easy doors. Make weak passwords hard to use. And make strange login behavior stand out before it becomes a bigger problem. Once these basics are solid attackers lose the quiet advantage they depend on.

• Strong Passphrases and Lockout. Use long natural passphrases that avoid predictable patterns and pair them with smart lockout rules that slow repeated failures. A short delay after several bad attempts breaks the attacker flow while keeping the user experience smooth. 
• Reliable Multi Step Sign In. MFA adds a second layer that attackers cannot guess or brute force. Even if a password leaks the intruder still hits a hard stop. A quick verification through an app or code keeps things easy for users while removing the silent advantage.
• Biometric Identity Checks. Biometric sign in adds a unique proof of identity that bots cannot imitate. A fingerprint or face scan cannot be sprayed or mass guessed which shuts down automated attacks before they gain any ground.
• Zero Trust Access Control. Treat every login as untrusted until it proves otherwise. Check device health behavior and context before allowing access. When something looks unusual, increase verification. When things look normal stay smooth. 
• Behavior Based Login Monitoring. Watch for strange activity like sudden failure spikes or logins from unexpected places. Block weak or leaked passwords to remove the attacker’s easiest guesses. 

Building an Effective Password Protection Framework

Start by adding a platform that closes easy doors fast. Infisign brings two pillars for this job. UniFed for unified customer identity. And an IAM Suite for the workforce. Together they cut password risk. They add strong access controls. They spot abuse early. They keep sign in simple for real users.

Infisign Authentication and Access Control

Infisign Smart Multi Factor Authentication

• You want security that stays strong without breaking workflow. Infisign’s adaptive multi factor authentication runs smoothly across cloud apps, on premises systems and hybrid setups. It stops phishing and blocks unauthorized access while keeping sign-ins quick and simple for your team.

Why Infisign Adaptive MFA Works

• Adjusts authentication checks based on location, device health, user role and real time risk signals
• Works with the authenticator apps and identity tools your team already uses
• Extends SSO and MFA to legacy and on premises applications that traditional platforms cannot cover
• Enables biometric authentication through face, iris or fingerprint and supports device bound passkeys that cannot be shared or phished
• Offers a full passwordless experience using biometrics passkeys OTPs or QR based approvals

Supported Authentication Methods

• Biometric verification through face or fingerprint on trusted devices
• FIDO2 and WebAuthn hardware keys for passwordless and phishing resistant access
• Time based one time passcodes from authenticator apps
• Push approvals on known devices for fast confirmation
• Email or SMS codes used only as limited fallback
• NAG and MPWA support to enable biometric login for legacy and on premises apps that do not support modern MFA

Infisign Passwordless Authentication‍

• ‍Infisign’s passwordless feature removes passwords completely. It uses biometrics and device passkeys built on FIDO2 and WebAuthn. Infisign supports biometric authentication through face, fingerprint, and iris verification on trusted devices. Magic links open direct access from your trusted device. You sign in once and reach all your apps. Zero knowledge proof keeps your secrets safe from phishing because no one can steal what you never share. 

Infisign Conditional Access Policies‍

• Infisign sees when a user with a basic role tries to open admin tools or download sensitive files. It uses conditional access based on real time risk to stop the action. You get alerts or audit logs when something odd happens. It ends the risk of costly breaches by reacting in the moment to protect your system.

Infisign Login Thresholds and IP Throttling‍

• Infisign sets firm limits on every login attempt. It monitors requests in real time and slows access when behavior looks unsafe. You stop brute force attacks early and protect uptime. The system stays light under load and keeps your authentication layer secure even under pressure.

Infisign Network Access Gateway 

• Infisign Network Access Gateway brings modern identity protection to apps that cannot support SSO or MFA on their own. It gives a single smooth login path across cloud and on premises tools and applies strong checks at every request.

Infisign Identity and Automation

‍Infisign Easy and Unlimited Directory Sync‍

• Infisign joins all your directories in one simple flow. It connects with HRIS systems to keep employee data current. You see instant updates when roles change or users move. There are no hidden limits or extra costs.

Infisign Automated User and Access Management‍

• Infisign keeps user management effortless. It automatically grants and removes access so your IT team can focus on important work instead of manual tasks. You handle user lifecycle tasks automatically with provisioning and deprovisioning across apps.

Infisign Privileged Access Management‍

• ‍Infisign’s PAM feature grants admin rights only when needed and they vanish when the task is done. You get access for the time you must act and no longer. Each privileged action is logged in real time so you can see who did what and when. The principle of least privilege is built in by default so standing access is removed. Third party experts get access through just in time access instead of permanent rights. You reduce risk and keep full audit records for visibility and control.

Infisign Security and Governance

Infisign MPWA and Password Vault‍

• Infisign uses MPWA to give passwordless login for old applications through secure automation that replaces manual credentials. Its Password Vault stores all secrets in a protected space and keeps them hidden from users. Both features let legacy tools run safely inside a modern identity framework without replacing existing systems or changing how they work.

Infisign Non Human Identity‍

• Infisign treats bot and API accounts with the same care as human users. It removes passwords completely from these accounts. Rules define how they connect and what they can reach. You control access for every machine identity and monitor service accounts tokens and certificates the same way you watch user logins. The same strong protections apply to human and non human users.

Infisign Compliance and Auditing‍

• Every organisation must follow strict data protection and privacy rules. Infisign solves this with built in Compliance and Auditing tools that keep everything transparent, accurate and automatic. Infisign provides complete visibility into every login and user activity so you can meet compliance requirements easily without creating reports manually. These capabilities align with what you find in full IAM compliance frameworks and help prove security across your environment.

Stop password spraying before it hits your business. Experience how Infisign makes every login secure and effortless. Book your demo and see passwordless protection in real time.

FAQs

What are the three main types of password attacks?

• Brute force guesses many passwords on one account. 
• Password spraying tries one common password across many accounts. 
• Credential stuffing uses leaked username and password pairs to log in directly.
  

How can you protect against password spray?

You can protect against a password spraying attack by using long unique passphrases and turning on MFA so a guessed password is not enough. Block common or leaked passwords and add short delays after failed attempts to break automated scripts. Keep monitoring sign in activity for strange timing or unusual locations to catch early probing.

What are the signs of a password spray attack?‍

Multiple accounts show failed logins using the same password. Attempts come from unfamiliar regions or devices. Slow repeated tries spread over time. Some accounts may suddenly create mail rules. 

What are the risks of password spraying?‍

One weak password can give attackers access to email files and internal tools. They can escalate privileges, move laterally, steal data, disrupt operations and trigger financial or reputational damage.