diff --git a/ChangeLog b/ChangeLog
index c5be981b..013cba89 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -56,6 +56,7 @@ ver. 0.10.6-dev (20??/??/??) - development edition
   - `normal`: matches 401 with supplied username only
   - `ddos`: matches 401 without supplied username only
   - `aggressive`: matches 401 and any variant (with and without username)
+* `filter.d/sshd.conf`: normalizing of user pattern in all RE's, allowing empty user (gh-2749)
 
 ### New Features
 * new filter and jail for GitLab recognizing failed application logins (gh-2689)
diff --git a/config/filter.d/sshd.conf b/config/filter.d/sshd.conf
index 31e61b96..4c86dca0 100644
--- a/config/filter.d/sshd.conf
+++ b/config/filter.d/sshd.conf
@@ -25,7 +25,7 @@ __pref = (?:(?:error|fatal): (?:PAM: )?)?
 __suff = (?: (?:port \d+|on \S+|\[preauth\])){0,3}\s*
 __on_port_opt = (?: (?:port \d+|on \S+)){0,2}
 # close by authenticating user:
-__authng_user = (?: (?:invalid|authenticating) user <F-USER>\S+|.+?</F-USER>)?
+__authng_user = (?: (?:invalid|authenticating) user <F-USER>\S+|.*?</F-USER>)?
 
 # for all possible (also future) forms of "no matching (cipher|mac|MAC|compression method|key exchange method|host key type) found",
 # see ssherr.c for all possible SSH_ERR_..._ALG_MATCH errors.
@@ -44,18 +44,18 @@ cmnfailre = ^[aA]uthentication (?:failure|error|failed) for <F-USER>.*</F-USER>
             ^Failed <cmnfailed> for (?P<cond_inv>invalid user )?<F-USER>(?P<cond_user>\S+)|(?(cond_inv)(?:(?! from ).)*?|[^:]+)</F-USER> from <HOST>%(__on_port_opt)s(?: ssh\d*)?(?(cond_user): |(?:(?:(?! from ).)*)$)
             ^<F-USER>ROOT</F-USER> LOGIN REFUSED FROM <HOST>
             ^[iI](?:llegal|nvalid) user <F-USER>.*?</F-USER> from <HOST>%(__suff)s$
-            ^User <F-USER>.+</F-USER> from <HOST> not allowed because not listed in AllowUsers%(__suff)s$
-            ^User <F-USER>.+</F-USER> from <HOST> not allowed because listed in DenyUsers%(__suff)s$
-            ^User <F-USER>.+</F-USER> from <HOST> not allowed because not in any group%(__suff)s$
+            ^User <F-USER>\S+|.*?</F-USER> from <HOST> not allowed because not listed in AllowUsers%(__suff)s$
+            ^User <F-USER>\S+|.*?</F-USER> from <HOST> not allowed because listed in DenyUsers%(__suff)s$
+            ^User <F-USER>\S+|.*?</F-USER> from <HOST> not allowed because not in any group%(__suff)s$
             ^refused connect from \S+ \(<HOST>\)
             ^Received <F-MLFFORGET>disconnect</F-MLFFORGET> from <HOST>%(__on_port_opt)s:\s*3: .*: Auth fail%(__suff)s$
-            ^User <F-USER>.+</F-USER> from <HOST> not allowed because a group is listed in DenyGroups%(__suff)s$
-            ^User <F-USER>.+</F-USER> from <HOST> not allowed because none of user's groups are listed in AllowGroups%(__suff)s$
+            ^User <F-USER>\S+|.*?</F-USER> from <HOST> not allowed because a group is listed in DenyGroups%(__suff)s$
+            ^User <F-USER>\S+|.*?</F-USER> from <HOST> not allowed because none of user's groups are listed in AllowGroups%(__suff)s$
             ^<F-NOFAIL>%(__pam_auth)s\(sshd:auth\):\s+authentication failure;</F-NOFAIL>(?:\s+(?:(?:logname|e?uid|tty)=\S*)){0,4}\s+ruser=<F-ALT_USER>\S*</F-ALT_USER>\s+rhost=<HOST>(?:\s+user=<F-USER>\S*</F-USER>)?%(__suff)s$
             ^maximum authentication attempts exceeded for <F-USER>.*</F-USER> from <HOST>%(__on_port_opt)s(?: ssh\d*)?%(__suff)s$
-            ^User <F-USER>.+</F-USER> not allowed because account is locked%(__suff)s
+            ^User <F-USER>\S+|.*?</F-USER> not allowed because account is locked%(__suff)s
             ^<F-MLFFORGET>Disconnecting</F-MLFFORGET>(?: from)?(?: (?:invalid|authenticating)) user <F-USER>\S+</F-USER> <HOST>%(__on_port_opt)s:\s*Change of username or service not allowed:\s*.*\[preauth\]\s*$
-            ^Disconnecting: Too many authentication failures(?: for <F-USER>.+?</F-USER>)?%(__suff)s$
+            ^Disconnecting: Too many authentication failures(?: for <F-USER>\S+|.*?</F-USER>)?%(__suff)s$
             ^<F-NOFAIL>Received <F-MLFFORGET>disconnect</F-MLFFORGET></F-NOFAIL> from <HOST>%(__on_port_opt)s:\s*11:
             <mdre-<mode>-other>
             ^<F-MLFFORGET><F-MLFGAINED>Accepted \w+</F-MLFGAINED></F-MLFFORGET> for <F-USER>\S+</F-USER> from <HOST>(?:\s|$)
diff --git a/fail2ban/tests/files/logs/sshd b/fail2ban/tests/files/logs/sshd
index 1bf9d913..9fff416a 100644
--- a/fail2ban/tests/files/logs/sshd
+++ b/fail2ban/tests/files/logs/sshd
@@ -321,6 +321,11 @@ Mar 15 09:21:02 host sshd[2717]: Connection closed by 192.0.2.212 [preauth]
 # failJSON: { "time": "2005-07-18T17:19:11", "match": true , "host": "192.0.2.4", "desc": "ddos: disconnect on preauth phase, gh-2115" }
 Jul 18 17:19:11 srv sshd[2101]: Disconnected from 192.0.2.4 port 36985 [preauth]
 
+# failJSON: { "time": "2005-06-06T04:17:04", "match": true , "host": "192.0.2.68", "dns": null, "user": "", "desc": "empty user, gh-2749" }
+Jun  6 04:17:04 host sshd[1189074]: Invalid user  from 192.0.2.68 port 34916
+# failJSON: { "time": "2005-06-06T04:17:09", "match": true , "host": "192.0.2.68", "dns": null, "user": "", "desc": "empty user, gh-2749" }
+Jun  6 04:17:09 host sshd[1189074]: Connection closed by invalid user  192.0.2.68 port 34916 [preauth]
+
 # filterOptions: [{"mode": "extra"}, {"mode": "aggressive"}]
 
 # several other cases from gh-864: