What Is an App Secret in Azure AD and Why Use It
An app secret in Azure AD is a private code. It helps your app show who it is. You use this secret like a password with Azure AD. About half of all Azure AD apps use app secrets to log in. This makes them a popular choice. Many developers choose app secrets because they are easy to use. This is true for smaller projects. But, attackers have tried to steal app secrets in some security problems. This shows we must be careful with them.
Key Takeaways
An app secret in Azure AD is like a password. It helps your app show who it is in a safe way.
Use app secrets for easy or quick projects. Always keep them safe and change them often.
Put app secrets in safe places like Azure Key Vault. Do not put them in your code.
Change app secrets often and set alerts. This helps you avoid problems from expired secrets.
For better safety, use certificates or managed identities if you can. These are stronger than app secrets.
App Secrets in Azure AD
What Is an App Secret
An app secret in Azure AD is a special code. It helps your app show who it is. You use this code like a password with Azure AD. Each app secret has three main parts. These are the secret value, a unique Secret ID, and an expiration date. The Secret ID helps you keep track of secrets. This is useful if you use tools like Microsoft Graph API. You can make, find, or delete secrets using these details. Azure AD keeps these secrets safe. You can choose who can see or change them.
Note: You only see the secret value one time, right after you make it. You must save it somewhere safe. You cannot look at it again later.
The way an app secret is set up helps you manage your app’s credentials. You can pick how long a secret lasts. You can remove it when you do not need it anymore. This helps keep your app safe.
Why Use App Secrets
You might use app secrets in Azure AD for different reasons. App secrets are good when you want a simple way for your app to sign in. Many developers use them for testing or building apps because they are easy to make and use. App secrets are also needed in some OAuth 2.0 flows, like the client credential flow.
Here are some common times when app secrets are used:
You make a small app or a test project.
You work in a development or debugging setting.
You cannot use certificates or managed identities.
You need a fast way to set up authentication.
App secrets are easier to use than certificates. You do not have to do extra steps. But you should change secrets often and keep them safe. If someone gets your app secret, they can get into your app as you. Azure AD protects secrets with encryption, role-based access control, and audit logs. You should not put secrets in your code or share them in unsafe ways.
⚠️ Tip: For better security, use managed identities or certificates if you can. App secrets are best for simple or short-term needs.
You can see how app secrets are different from other ways to sign in in the table below:
Azure AD gives you choices. You should pick what works for you and keeps your app safe.
How App Secrets Work
Authentication Flow
When your app uses an app secret in Azure AD, it follows a clear process to prove its identity. This process is called the authentication flow. You use this flow when your app needs to talk to Azure AD or another service without a user involved.
Here is what usually happens:
You register your app in Azure AD.
You create a client secret for your app.
You set up permissions for your app to access other services or APIs.
You give your app the right to use these permissions.
Your app sends its client ID and client secret to Azure AD to ask for an access token.
Azure AD checks the secret. If it matches, Azure AD gives your app an access token.
Your app uses this access token to call APIs or services. The client secret acts like a password. Azure AD checks the secret against what it has stored. If the secret is correct and not expired, your app gets access. You use this flow when no user signs in, and your app needs to act on its own.
Note: The client ID is public. Only the client secret must stay private.
Expiration and Rotation
App secrets in Azure AD do not last forever. Each secret has an expiration date. By default, the maximum expiration period is two years if you create the secret in the Azure portal. After this time, the secret stops working. You must create a new secret to keep your app running.
You should not wait until the last minute to rotate secrets. Many organizations set up alerts to warn you 90 days before a secret expires. You might see a critical alert 30 days before expiration. Regular rotation helps keep your app safe. Some teams use automation to check for secrets that will expire soon. They remove old secrets, create new ones, and update their apps.
Rotate secrets often to lower risk.
Use tools like Azure Key Vault to help manage secrets.
Set up alerts so you never miss an expiration.
🔒 Tip: Regular rotation and short expiration periods help protect your app from attacks.
Manage App Secrets
Create an App Secret
You can create an app secret in Azure AD using the Azure portal. Here is what you do:
Sign in to the Azure Portal.
Search for "Azure Active Directory."
Click "App registrations" and pick your app.
Select "Certificates & secrets" from the menu.
Go to the "Client secrets" tab.
Click "New client secret."
Type a description and choose how long the secret should last.
Click "Add" to make the secret.
Copy the secret value right away. You will not see it again after you leave the page.
Note: You need special permissions to create app secrets. The main permission is called
microsoft.directory/applications/credentials/update.
Store and Secure Secrets
You must keep app secrets safe. Never put secrets in your code or share them in public places. Use secret management tools to help you. Azure Key Vault is the main tool for storing secrets. It keeps secrets encrypted and lets you control who can see them. Managed identities let your app get secrets without storing them in code. You can also use role-based access control to limit who can access secrets.
Here are some best practices:
Store secrets in Azure Key Vault or a secure key store.
Use tags to track when secrets need to be changed.
Set up network rules so only trusted apps can reach your secrets.
Scan your code for secrets before you share it.
⚠️ Tip: Always save the secret value when you create it. You cannot get it back later.
Monitor and Alert
You can watch how secrets are used and set up alerts for changes. Use Azure Monitor to track when someone creates a new secret. You can also use PowerShell scripts to find secrets that will expire soon. Export secret data to a file and review it often. Set up alerts to warn you before secrets expire. This helps you renew secrets on time and avoid problems.
Some tools help you scan for secrets in code and pipelines. You can also use audit logs to see who used a secret and when. Automation can help you rotate secrets and update your app without downtime.
🔒 Tip: Keep at least two secrets active during rotation. This prevents your app from stopping if one secret expires.
Risks and Alternatives
Security Risks
There are some risks when you use app secrets in Azure AD. Attackers try to find weak spots in your security. If you do not keep secrets safe, you could lose your app or data. Here are some common risks:
Secrets can show up in code, logs, or public places.
You might put secrets right in your app files.
Old secrets can expire and break your app.
Weak passwords make it easy for attackers to guess secrets.
Phishing or malware can steal secrets from you.
You might give too many people access or forget to change secrets.
If someone gets your app secret, they can get into your Azure resources. This can cause data leaks or loss of control. You should use strong rules and change secrets often. You can also use multi-factor authentication and conditional access to make things safer.
⚠️ Tip: Only give people the access they need. Do not give extra permissions.
Certificate Authentication
Certificates are a stronger way to prove your app’s identity in Azure AD. You use certificates instead of secrets. Certificates use cryptography, which is harder to break. Here is why certificates are better:
Tokens signed with certificates expire fast, so attackers have less time.
Certificates are kept safe, often in special hardware.
You cannot see or copy certificates from Azure, which keeps them safe.
Trusted groups or you can make certificates yourself.
You need to create, install, and change certificates sometimes. This is more work than using app secrets. But certificates give you better security and protect your app from attacks.
🛡️ Note: Microsoft says to use certificates for production apps. They help lower the risk of secrets getting out.
Managed Identities
Managed identities are another way to keep your app safe in Azure AD. You do not need to keep secrets or certificates. Azure makes and manages the identity for you. Here are the main benefits:
Credentials change by themselves.
Easy to use for Azure resources.
You can check what happens with Azure Monitor.
Great for CI/CD pipelines.
Managed identities help stop leaks and make your app easier to run. You do not need to worry about secrets expiring or changing them yourself. Azure does all the work in the background.
💡 Tip: Use managed identities for Azure resources if you can. This means you do not have to handle secrets yourself.
Knowing how to handle app secrets in Azure AD keeps your apps safe. You should make secrets last for a short time. Change them often and watch how they are used. Here are some good tips:
Set up alerts so you know when secrets will expire.
Try to use certificates or managed identities if you can.
Give only the permissions needed and check who has access often.
Look at how you use app secrets now. Making your security better today helps keep your apps and data safe later.
FAQ
What is the difference between an app secret and a certificate in Azure AD?
An app secret is like a password for your app. A certificate uses special math to keep things safer. App secrets are good for easy or small jobs. Certificates are better for important or big apps.
What happens if you lose your app secret value?
You cannot get the secret back if you lose it. You must make a new secret in Azure AD. Always save your secret in a safe spot when you create it.
What is the best way to store app secrets?
You should use Azure Key Vault to keep secrets safe. It locks secrets and controls who can see them. Never put secrets in your code or share them in public.
What should you do when an app secret expires?
You need to make a new secret before the old one ends. Change your app to use the new secret. Set alerts so you remember before it expires.
What is a managed identity in Azure AD?
A managed identity is made by Azure for your app. You do not need to handle secrets or certificates. Azure takes care of everything for you. Managed identities work best with Azure resources.