diff --git a/ChangeLog b/ChangeLog
index 398296f3..c405c8af 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -57,7 +57,8 @@ ver. 0.10.5-dev-1 (20??/??/??) - development edition
* `filter.d/sshd.conf`:
- matches `Bad protocol version identification` in `ddos` and `aggressive` modes (gh-2404).
- captures `Disconnecting ...: Change of username or service not allowed` (gh-2239, gh-2279)
- - captures `Disconnected from ... [preauth]` (`extra`/`aggressive` mode and preauth phase only, gh-2239, gh-2279)
+ - captures `Disconnected from ... [preauth]`, preauth phase only, different handling by `extra`
+ (with supplied user only) and `ddos`/`aggressive` mode (gh-2115, gh-2239, gh-2279)
* `filter.d/mysqld-auth.conf`:
- MYSQL 8.0.13 compatibility (log-error-verbosity = 3), log-format contains few additional words
enclosed in brackets after "[Note]" (gh-2314)
diff --git a/config/filter.d/sshd.conf b/config/filter.d/sshd.conf
index b10f5acb..d764a076 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 = (?: authenticating user \S+|.+?)?
+__authng_user = (?: (?:invalid|authenticating) user \S+|.+?)?
# 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.
@@ -57,31 +57,32 @@ cmnfailre = ^[aA]uthentication (?:failure|error|failed) for .*
^Disconnecting(?: from)?(?: (?:invalid|authenticating)) user \S+ %(__on_port_opt)s:\s*Change of username or service not allowed:\s*.*\[preauth\]\s*$
^Disconnecting: Too many authentication failures(?: for .+?)?%(__suff)s$
^Received disconnect from %(__on_port_opt)s:\s*11:
- ^Connection closed by%(__authng_user)s -suff-onclosed>
+ -other>
^Accepted \w+ for \S+ from (?:\s|$)
mdre-normal =
# used to differentiate "connection closed" with and without `[preauth]` (fail/nofail cases in ddos mode)
-mdrp-normal-suff-onclosed = (?:%(__suff)s|\s*)$
+mdre-normal-other = ^(Connection closed|Disconnected) (?:by|from)%(__authng_user)s (?:%(__suff)s|\s*)$
mdre-ddos = ^Did not receive identification string from
^Bad protocol version identification '.*' from
^Connection reset by
- ^Connection closed by%(__authng_user)s %(__on_port_opt)s\s+\[preauth\]\s*$
^SSH: Server;Ltype: (?:Authname|Version|Kex);Remote: -\d+;[A-Z]\w+:
^Read from socket failed: Connection reset by peer
-mdrp-ddos-suff-onclosed = %(__on_port_opt)s\s*$
+# same as mdre-normal-other, but as failure (without ) and [preauth] only:
+mdre-ddos-other = ^(Connection closed|Disconnected) (?:by|from)%(__authng_user)s %(__on_port_opt)s\s+\[preauth\]\s*$
mdre-extra = ^Received disconnect from %(__on_port_opt)s:\s*14: No supported authentication methods available
^Unable to negotiate with %(__on_port_opt)s: no matching <__alg_match> found.
^Unable to negotiate a <__alg_match>
^no matching <__alg_match> found:
- ^Disconnected(?: from)?(?: (?:invalid|authenticating)) user \S+ %(__on_port_opt)s \[preauth\]\s*$
-mdrp-extra-suff-onclosed = %(mdrp-normal-suff-onclosed)s
+# part of mdre-ddos-other, but user name is supplied (invalid/authenticating) on [preauth] phase only:
+mdre-extra-other = ^Disconnected(?: from)?(?: (?:invalid|authenticating)) user \S+|.*? %(__on_port_opt)s \[preauth\]\s*$
mdre-aggressive = %(mdre-ddos)s
%(mdre-extra)s
-mdrp-aggressive-suff-onclosed = %(mdrp-ddos-suff-onclosed)s
+# mdre-extra-other is fully included within mdre-ddos-other:
+mdre-aggressive-other = %(mdre-ddos-other)s
cfooterre = ^Connection from
diff --git a/fail2ban/tests/files/logs/sshd b/fail2ban/tests/files/logs/sshd
index efedb423..a5f64939 100644
--- a/fail2ban/tests/files/logs/sshd
+++ b/fail2ban/tests/files/logs/sshd
@@ -308,6 +308,9 @@ Mar 15 09:21:01 host sshd[2717]: Connection closed by 192.0.2.212 [preauth]
# failJSON: { "time": "2005-03-15T09:21:02", "match": true , "host": "192.0.2.212", "desc": "DDOS mode causes failure on close within preauth stage" }
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]
+
# filterOptions: [{"mode": "extra"}, {"mode": "aggressive"}]
# several other cases from gh-864: