diff --git a/config/filter.d/dovecot.conf b/config/filter.d/dovecot.conf
index 9c817720..c55061c3 100644
--- a/config/filter.d/dovecot.conf
+++ b/config/filter.d/dovecot.conf
@@ -14,7 +14,7 @@ _daemon = (?:dovecot(?:-auth)?|auth)
 prefregex = ^%(__prefix_line)s(?:%(_auth_worker)s(?:\([^\)]+\))?: )?(?:%(__pam_auth)s(?:\(dovecot:auth\))?: |(?:pop3|imap|managesieve|submission)-login: )?(?:Info: )?%(_auth_worker_info)s<F-CONTENT>.+</F-CONTENT>$
 
 failregex = ^authentication failure; logname=<F-ALT_USER1>\S*</F-ALT_USER1> uid=\S* euid=\S* tty=dovecot ruser=<F-USER>\S*</F-USER> rhost=<HOST>(?:\s+user=<F-ALT_USER>\S*</F-ALT_USER>)?\s*$
-            ^(?:Aborted login|Disconnected|Remote closed connection|Client has quit the connection)(?::(?: [^ \(]+)+)? \((?:auth failed, \d+ attempts(?: in \d+ secs)?|tried to use (?:disabled|disallowed) \S+ auth|proxy dest auth failed)\):(?: user=<<F-USER>[^>]*</F-USER>>,)?(?: method=\S+,)? rip=<HOST>(?:[^>]*(?:, session=<\S+>)?)\s*$
+            ^(?:Aborted login|Disconnected|Remote closed connection|Client has quit the connection)(?:: (?:[^\(]+|\w+\([^\)]*\))+)? \((?:auth failed, \d+ attempts(?: in \d+ secs)?|tried to use (?:disabled|disallowed) \S+ auth|proxy dest auth failed)\):(?: user=<<F-USER>[^>]*</F-USER>>,)?(?: method=\S+,)? rip=<HOST>(?:[^>]*(?:, session=<\S+>)?)\s*$
             ^pam\(\S+,<HOST>(?:,\S*)?\): pam_authenticate\(\) failed: (?:User not known to the underlying authentication module: \d+ Time\(s\)|Authentication failure \([Pp]assword mismatch\?\)|Permission denied)\s*$
             ^[a-z\-]{3,15}\(\S*,<HOST>(?:,\S*)?\): (?:[Uu]nknown user|[Ii]nvalid credentials|[Pp]assword mismatch)
             <mdre-<mode>>
diff --git a/fail2ban/tests/files/logs/dovecot b/fail2ban/tests/files/logs/dovecot
index 6bcf8c5b..e780411b 100644
--- a/fail2ban/tests/files/logs/dovecot
+++ b/fail2ban/tests/files/logs/dovecot
@@ -107,6 +107,8 @@ Jul 26 11:12:19 hostname dovecot: imap-login: Disconnected: Too many invalid com
 
 # failJSON: { "time": "2004-08-28T06:38:51", "match": true , "host": "192.0.2.3" }
 Aug 28 06:38:51 s166-62-100-187 dovecot: imap-login: Disconnected (auth failed, 1 attempts in 9 secs): user=<administrator@example.com>, method=PLAIN, rip=192.0.2.3, lip=192.168.1.2, TLS: Disconnected, TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
+# failJSON: { "time": "2004-08-28T06:38:52", "match": true , "host": "192.0.2.4", "desc": "open parenthesis in optional part between Disconnected and (auth failed ...), gh-3210" }
+Aug 28 06:38:52 s166-62-100-187 dovecot: imap-login: Disconnected: Connection closed: read(size=1003) failed: Connection reset by peer (auth failed, 1 attempts in 0 secs): user=<test@example.com>, rip=192.0.2.4, lip=127.0.0.19, session=<Lsz0Oo7WXti3b7xe>
 
 # failJSON: { "time": "2004-08-29T03:17:18", "match": true , "host": "192.0.2.133" }
 Aug 29 03:17:18 server dovecot: submission-login: Client has quit the connection (auth failed, 1 attempts in 2 secs): user=<user1>, method=LOGIN, rip=192.0.2.133, lip=0.0.0.0