Mailster AWS SES Integration Signature version 3 Error

Hi,

I have been using the plugin for long and it is working all fine but recently I received this mail from AWS stating I’m using signature 3 for AWS and I need to change it to signature version 4. I don’t know what to do.

I am using mailster v2.4.

Here’s the email from AWS.
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Amazon Simple Email Service (SES) had extended support for Signature Version 3 to February 28th, 2021. To continue to use Amazon SES, you must migrate to Signature Version 4 which offers enhanced security for authentication and authorization of Amazon SES customers.

We have identified that, between 2021-05-03 and 2021-05-10, your AWS account 174228166529 used Signature Version 3 to call Amazon SES APIs in the us-east-1 Region.

Your Signature Version 3 requests were identified to be originating from:
– IAM Users: arn:aws:iam::174228166529:user/KOSA
– IPs: 162.144.20.85
– User Agents: WordPress/5.7.1; https://saahm.net

Your Signature Version 3 requests were identified to be using the following SES actions:
– APIs: VerifyEmailIdentity, GetSendQuota, SendRawEmail, ListIdentities

Example Request ID using Signature Version 3: a1fa9ff2-b7f1-4ce8-9afe-3a3843c2ad5a

The page I need help with: [log in to see the link]