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Just setting a string to null or calling the GC will not help here. It might delete the reference to the value, but not the value itself. After GC, it may be overwritten, but there is no guarantee that it will happend anytime soon.

What you need instead is something aking to a SecureString, that implements a Dispose method and some obfuscation. However, the security it provides is limited:

We don't recommend that you use the SecureString class for new development. For more information, see SecureString shouldn't be used on GitHub.

 

SecureString is a string type that provides a measure of security. It tries to avoid storing potentially sensitive strings in process memory as plain text. (For limitations, however, see the How secure is SecureString? section.)

The problem here is that if there is sufficently advanced malware with sufficiently high priviliges on your system, no secrets are safe no matter what fancy C# types you wrap them in. So I am not sure this is a problem with a solution.

If you do use a secure string, think about how you get the value into and out of it. If it passes through an ordinary string, you have gained absolutely nothing.

Just setting a string to null or calling the GC will not help here. It might delete the reference to the value, but not the value itself. After GC, it may be overwritten, but there is no guarantee that it will happend anytime soon.

What you need instead is something aking to a SecureString, that implements a Dispose method and some obfuscation. However, the security it provides is limited:

We don't recommend that you use the SecureString class for new development. For more information, see SecureString shouldn't be used on GitHub.

SecureString is a string type that provides a measure of security. It tries to avoid storing potentially sensitive strings in process memory as plain text. (For limitations, however, see the How secure is SecureString? section.)

The problem here is that if there is sufficently advanced malware with sufficiently high priviliges on your system, no secrets are safe no matter what fancy C# types you wrap them in. So I am not sure this is a problem with a solution.

If you do use a secure string, think about how you get the value into and out of it. If it passes through an ordinary string, you have gained absolutely nothing.

Just setting a string to null or calling the GC will not help here. It might delete the reference to the value, but not the value itself. After GC, it may be overwritten, but there is no guarantee that it will happend anytime soon.

What you need instead is a SecureString. It implements a Dispose method. Just be careful about how you get your secret value into the secure string - if you just copy it from an ordinary string you haven't really solved anything.

Do note that you should only think of this as a form of obfuscation. If there is sufficently advanced malware with sufficiently high priviliges on your system, no secrets are safe no matter what fancy C# types you wrap them in.

Just setting a string to null or calling the GC will not help here. It might delete the reference to the value, but not the value itself. After GC, it may be overwritten, but there is no guarantee that it will happend anytime soon.

What you need instead is something aking to a SecureString, that implements a Dispose method and some obfuscation. However, the security it provides is limited:

We don't recommend that you use the SecureString class for new development. For more information, see SecureString shouldn't be used on GitHub.

SecureString is a string type that provides a measure of security. It tries to avoid storing potentially sensitive strings in process memory as plain text. (For limitations, however, see the How secure is SecureString? section.)

The problem here is that if there is sufficently advanced malware with sufficiently high priviliges on your system, no secrets are safe no matter what fancy C# types you wrap them in. So I am not sure this is a problem with a solution.

If you do use a secure string, think about how you get the value into and out of it. If it passes through an ordinary string, you have gained absolutely nothing.

Just setting a string to null or calling the GC will not help here. It might delete the reference to the value, but not the value itself. After GC, it may be overwritten, but there is no guarantee that it will happend anytime soon.

What you need instead is a SecureString. It implements a Dispose method that you can call to wipe the value from memory. Just be careful about how you get your secret value into the secure string - if you just copy it from an ordinary string you haven't really solved anything.

Just setting a string to null or calling the GC will not help here. It might delete the reference to the value, but not the value itself. After GC, it may be overwritten, but there is no guarantee that it will happend anytime soon.

What you need instead is a SecureString. It implements a Dispose method. Just be careful about how you get your secret value into the secure string - if you just copy it from an ordinary string you haven't really solved anything.

Do note that you should only think of this as a form of obfuscation. If there is sufficently advanced malware with sufficiently high priviliges on your system, no secrets are safe no matter what fancy C# types you wrap them in.