Maven password encryption BadPaddingException

I'm trying to encrypt a server password in my settings.xml and I'm getting this exception when trying to deploy an artifact.

Caused by: javax.crypto.BadPaddingException: Given final block not properly padded
    at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:811)
    at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:676)
    at com.sun.crypto.provider.AESCipher.engineDoFinal(AESCipher.java:313)
    at javax.crypto.Cipher.doFinal(Cipher.java:2087)
    at org.sonatype.plexus.components.cipher.PBECipher.decrypt64(PBECipher.java:185)
    ... 18 more

here's the excerpt from the xml

<server>
            <id>server</id>
            <username>username</username>
            <password>{N8AF8BmQ5x8HZX/yrlrP1QiKNMEdoXWyBFZd/*zIabY=}</password> 
        </server>

the same exception is also happening for my master password, I just followed the instructions here
https://maven.apache.org/guides/mini/guide-encryption.html
created a security-settings.xml like in the guide, executed these two commands and copied the encrypted passwords into the appropriate xml files.

mvn --encrypt-master-password <password>
mvn --encrypt-password <password>