Dovecot 2.4 - Users with mdbox configured storage log a "Permission Denied" error when logging in to their account

Symptoms

After upgrading to cPanel 132 and Dovecot 2.4, users with the mdbox mail storage format have an error similar to the following being logged in /var/log/maillog:

Error: file_dotlock_open(/usr/local/cpanel/etc/dovecot/virtual/spam/dovecot.list.index.log) failed: Permission denied (euid=1001(USER) egid=1003(USER) missing +w perm: /usr/local/cpanel/etc/dovecot/virtual/spam, dir owned by 0:0 mode=0755)
Error: Mailbox spamINBOX: file_dotlock_open(/usr/local/cpanel/etc/dovecot/virtual/spam/INBOX/dovecot.index.log) failed: Permission denied (euid=1001(USER) egid=1003(USER) missing +w perm: /usr/local/cpanel/etc/dovecot/virtual/spam/INBOX, dir owned by 0:0 mode=0755)
Error: file_dotlock_open(/usr/local/cpanel/etc/dovecot/virtual/sent/dovecot.list.index.log) failed: Permission denied (euid=1001(USER) egid=1003(USER) missing +w perm: /usr/local/cpanel/etc/dovecot/virtual/sent, dir owned by 0:0 mode=0755)
Error: Mailbox sentINBOX: file_dotlock_open(/usr/local/cpanel/etc/dovecot/virtual/sent/INBOX/dovecot.index.log) failed: Permission denied (euid=1001(USER) egid=1003(USER) missing +w perm: /usr/local/cpanel/etc/dovecot/virtual/sent/INBOX, dir owned by 0:0 mode=0755)

This is noted when the user simply accesses services like Webmail.

This does not cause an issue with any features found within the email account itself, as this is from the Dovecot logging process. The user is still able to access their Spam and Sent folders without issue.

Description

Dovecot 2.4 makes many changes to define users, including namespace changes put in place on users. Due to this, the Dovecot-log process is finding an incorrect path to write to the Dovecot log for the user, resulting in this notice. Logging to /var/log/maillog is not impacted.

We've opened an internal case for our development team to investigate this further. For reference, the case number is CPANEL-50746. Follow this article to receive an email notification when a solution is published in the product. 

Workaround

There is currently no workaround.