diff --git a/include/proxy/ftp/ctrl.h b/include/proxy/ftp/ctrl.h
index 9a64796..8c1ace6 100644
--- a/include/proxy/ftp/ctrl.h
+++ b/include/proxy/ftp/ctrl.h
@@ -1,6 +1,6 @@
 /*
  * ProFTPD - mod_proxy FTP control conn API
- * Copyright (c) 2012-2016 TJ Saunders
+ * Copyright (c) 2012-2020 TJ Saunders
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -35,6 +35,7 @@ int proxy_ftp_ctrl_handle_async(pool *p, conn_t *backend_conn,
 
 pr_response_t *proxy_ftp_ctrl_recv_resp(pool *p, conn_t *ctrl_conn,
   unsigned int *resp_nlines, int flags);
+int proxy_ftp_ctrl_send_abort(pool *p, conn_t *ctrl_conn, cmd_rec *cmd);
 int proxy_ftp_ctrl_send_cmd(pool *p, conn_t *ctrl_conn, cmd_rec *cmd);
 int proxy_ftp_ctrl_send_resp(pool *p, conn_t *ctrl_conn, pr_response_t *resp,
   unsigned int resp_nlines);
diff --git a/lib/proxy/ftp/ctrl.c b/lib/proxy/ftp/ctrl.c
index 5a09de0..45cba34 100644
--- a/lib/proxy/ftp/ctrl.c
+++ b/lib/proxy/ftp/ctrl.c
@@ -1,6 +1,6 @@
 /*
  * ProFTPD - mod_proxy FTP control conn routines
- * Copyright (c) 2012-2016 TJ Saunders
+ * Copyright (c) 2012-2020 TJ Saunders
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -26,6 +26,7 @@
 
 #include "proxy/netio.h"
 #include "proxy/ftp/ctrl.h"
+#include "proxy/tls.h"
 
 static const char *trace_channel = "proxy.ftp.ctrl";
 
@@ -366,6 +367,84 @@ pr_response_t *proxy_ftp_ctrl_recv_resp(pool *p, conn_t *ctrl_conn,
   return resp;
 }
 
+#ifndef TELNET_DM
+# define TELNET_DM	242
+#endif /* TELNET_DM */
+
+#ifndef TELNET_IAC
+# define TELNET_IAC	255
+#endif /* TELNET_IAC */
+
+#ifndef TELNET_IP
+# define TELNET_IP	244
+#endif /* TELNET_IP */
+
+int proxy_ftp_ctrl_send_abort(pool *p, conn_t *ctrl_conn, cmd_rec *cmd) {
+  int fd, res, use_tls, xerrno;
+  unsigned char buf[7];
+
+  if (p == NULL ||
+      ctrl_conn == NULL ||
+      cmd == NULL) {
+    errno = EINVAL;
+    return -1;
+  }
+
+  /* If we are proxying the ABOR command, preface it with the Telnet "Sync"
+   * mechanism, using OOB data.  If the receiving server supports this, it can
+   * generate a signal to interrupt any IO occurring on the backend server
+   * (such as when sendfile(2) is used).
+   *
+   * Note that such Telnet codes can only be used if we are NOT using TLS
+   * on the backend control connection.
+   */
+  use_tls = proxy_tls_using_tls();
+  if (use_tls != PROXY_TLS_ENGINE_OFF) {
+    return proxy_ftp_ctrl_send_cmd(p, ctrl_conn, cmd);
+  }
+
+  fd = PR_NETIO_FD(ctrl_conn->outstrm);
+
+  buf[0] = TELNET_IAC;
+  buf[1] = TELNET_IP;
+  buf[2] = TELNET_IAC;
+
+  pr_trace_msg(trace_channel, 9,
+    "sending Telnet abort code out-of-band to backend");
+  res = send(fd, &buf, 3, MSG_OOB);
+  xerrno = errno;
+
+  if (res < 0) {
+    pr_trace_msg(trace_channel, 1,
+      "error sending Telnet abort code out-of-band to backend: %s",
+      strerror(xerrno));
+    errno = xerrno;
+    return -1;
+  }
+
+  buf[0] = TELNET_DM;
+  buf[1] = 'A';
+  buf[2] = 'B';
+  buf[3] = 'O';
+  buf[4] = 'R';
+  buf[5] = '\r';
+  buf[6] = '\n';
+
+  pr_trace_msg(trace_channel, 9,
+    "proxied %s command from frontend to backend", (char *) cmd->argv[0]);
+  res = send(fd, &buf, 7, 0);
+  xerrno = errno;
+
+  if (res < 0) {
+    pr_trace_msg(trace_channel, 1,
+      "error sending Telnet DM code to backend: %s", strerror(xerrno));
+    errno = xerrno;
+    return -1;
+  }
+
+  return 0;
+}
+
 int proxy_ftp_ctrl_send_cmd(pool *p, conn_t *ctrl_conn, cmd_rec *cmd) {
   int res;
 
diff --git a/mod_proxy.c b/mod_proxy.c
index c1cde81..9d99312 100644
--- a/mod_proxy.c
+++ b/mod_proxy.c
@@ -84,28 +84,12 @@ static void proxy_timeoutidle_ev(const void *, void *);
 static void proxy_timeoutnoxfer_ev(const void *, void *);
 static void proxy_timeoutstalled_ev(const void *, void *);
 
-MODRET proxy_cmd(cmd_rec *cmd, struct proxy_session *proxy_sess,
+static int recv_resp(cmd_rec *cmd, struct proxy_session *proxy_sess,
     pr_response_t **rp) {
   int res, xerrno = 0;
   pr_response_t *resp;
   unsigned int resp_nlines = 0;
 
-  res = proxy_ftp_ctrl_send_cmd(cmd->tmp_pool, proxy_sess->backend_ctrl_conn,
-    cmd);
-  if (res < 0) {
-    xerrno = errno;
-    (void) pr_log_writefile(proxy_logfd, MOD_PROXY_VERSION,
-      "error sending %s to backend: %s", (char *) cmd->argv[0],
-      strerror(xerrno));
-
-    pr_response_add_err(R_500, _("%s: %s"), (char *) cmd->argv[0],
-      strerror(xerrno));
-    pr_response_flush(&resp_err_list);
-
-    errno = xerrno;
-    return PR_ERROR(cmd);
-  }
-
   resp = proxy_ftp_ctrl_recv_resp(cmd->tmp_pool, proxy_sess->backend_ctrl_conn,
     &resp_nlines, 0);
   if (resp == NULL) {
@@ -133,7 +117,7 @@ MODRET proxy_cmd(cmd_rec *cmd, struct proxy_session *proxy_sess,
     pr_response_flush(&resp_err_list);
 
     errno = xerrno;
-    return PR_ERROR(cmd);
+    return -1;
   }
 
   res = proxy_ftp_ctrl_send_resp(cmd->tmp_pool, proxy_sess->frontend_ctrl_conn,
@@ -143,15 +127,90 @@ MODRET proxy_cmd(cmd_rec *cmd, struct proxy_session *proxy_sess,
 
     pr_response_block(TRUE);
     errno = xerrno;
+    return -1;
+  }
+
+  if (rp != NULL) {
+    *rp = resp;
+  }
+
+  return 0;
+}
+
+MODRET proxy_cmd(cmd_rec *cmd, struct proxy_session *proxy_sess,
+    pr_response_t **rp) {
+  int res, xerrno = 0;
+
+  res = proxy_ftp_ctrl_send_cmd(cmd->tmp_pool, proxy_sess->backend_ctrl_conn,
+    cmd);
+  xerrno = errno;
+
+  if (res < 0) {
+    xerrno = errno;
+    (void) pr_log_writefile(proxy_logfd, MOD_PROXY_VERSION,
+      "error sending %s to backend: %s", (char *) cmd->argv[0],
+      strerror(xerrno));
+
+    pr_response_add_err(R_500, _("%s: %s"), (char *) cmd->argv[0],
+      strerror(xerrno));
+    pr_response_flush(&resp_err_list);
+
+    errno = xerrno;
+    return PR_ERROR(cmd);
+  }
+
+  if (recv_resp(cmd, proxy_sess, rp) < 0) {
     return PR_ERROR(cmd);
   }
 
   pr_response_block(TRUE);
+  return PR_HANDLED(cmd);
+}
 
-  if (rp != NULL) {
-    *rp = resp;
+MODRET proxy_abort(cmd_rec *cmd, struct proxy_session *proxy_sess,
+    pr_response_t **rp) {
+  int res, xerrno = 0;
+
+  res = proxy_ftp_ctrl_send_abort(cmd->tmp_pool,
+    proxy_sess->backend_ctrl_conn, cmd);
+  xerrno = errno;
+
+  if (res < 0) {
+    (void) pr_log_writefile(proxy_logfd, MOD_PROXY_VERSION,
+      "error sending %s to backend: %s", (char *) cmd->argv[0],
+      strerror(xerrno));
+
+    pr_response_add_err(R_500, _("%s: %s"), (char *) cmd->argv[0],
+      strerror(xerrno));
+    pr_response_flush(&resp_err_list);
+
+    errno = xerrno;
+    return PR_ERROR(cmd);
+  }
+
+  if (proxy_sess->backend_data_conn != NULL) {
+    pr_trace_msg(trace_channel, 19, "received ABOR on frontend connection, "
+      "closing backend data connection");
+    proxy_inet_close(session.pool, proxy_sess->backend_data_conn);
+    proxy_sess->backend_data_conn = NULL;
+  }
+
+  if (recv_resp(cmd, proxy_sess, rp) < 0) {
+    return PR_ERROR(cmd);
+  }
+
+  /* The ABOR command might have two responses, as when there is a data
+   * transfer in progress: one response for the data transfer, and one for
+   * handling the ABOR command itself.
+   */
+  if ((proxy_sess->frontend_sess_flags & SF_XFER) ||
+      (proxy_sess->backend_sess_flags & SF_XFER)) {
+    if (recv_resp(cmd, proxy_sess, rp) < 0) {
+      return PR_ERROR(cmd);
+    }
   }
 
+  pr_response_block(TRUE);
   return PR_HANDLED(cmd);
 }
 
@@ -2525,19 +2584,28 @@ MODRET proxy_data(struct proxy_session *proxy_sess, cmd_rec *cmd) {
       continue;
     }
 
-#if 0
     /* Any commands from the frontend client take priority */
-
-    /* NOTE: This is temporarily disabled, until I can better handle an
-     * ABOR command on the frontend control connection whilst in the middle
-     * of a data transfer.
-     */
     if (frontend_ctrlfd >= 0 &&
         FD_ISSET(frontend_ctrlfd, &rfds)) {
       proxy_process_cmd();
       pr_response_block(FALSE);
+
+      /* Check for closed frontend/backend data connections, as from an ABOR
+       * command.
+       */
+      if (session.d == NULL ||
+          proxy_sess->backend_data_conn == NULL) {
+        if (pr_data_get_timeout(PR_DATA_TIMEOUT_STALLED) > 0) {
+          pr_timer_remove(PR_TIMER_STALLED, ANY_MODULE);
+        }
+
+        pr_throttle_pause(bytes_transferred, TRUE);
+        pr_response_clear(&resp_list);
+        pr_response_clear(&resp_err_list);
+
+        return PR_HANDLED(cmd);
+      }
     }
-#endif
 
     if (src_data_conn != NULL &&
         datafd >= 0 &&
@@ -4357,6 +4425,23 @@ MODRET proxy_any(cmd_rec *cmd) {
         return PR_DECLINED(cmd);
       }
       break;
+
+    case PR_CMD_ABOR_ID:
+      mr = proxy_abort(cmd, proxy_sess, NULL);
+      if ((proxy_sess->frontend_sess_flags & SF_XFER) ||
+          (proxy_sess->backend_sess_flags & SF_XFER)) {
+        pr_trace_msg(trace_channel, 19, "received ABOR on frontend connection, "
+          "closing frontend data connection");
+
+        if (session.d != NULL) {
+          pr_inet_close(session.pool, proxy_sess->frontend_data_conn);
+          proxy_sess->frontend_data_conn = session.d = NULL;
+        }
+
+        proxy_sess->frontend_sess_flags &= ~SF_XFER;
+        proxy_sess->backend_sess_flags &= ~SF_XFER;
+      }
+      return mr;
   }
 
   /* If we are not connected to a backend server, then don't try to proxy
diff --git a/t/lib/ProFTPD/Tests/Modules/mod_proxy.pm b/t/lib/ProFTPD/Tests/Modules/mod_proxy.pm
index 920b2b1..f3cb66f 100644
--- a/t/lib/ProFTPD/Tests/Modules/mod_proxy.pm
+++ b/t/lib/ProFTPD/Tests/Modules/mod_proxy.pm
@@ -91,6 +91,11 @@ my $TESTS = {
     test_class => [qw(forking reverse)],
   },
 
+  proxy_reverse_abort => {
+    order => ++$order,
+    test_class => [qw(forking reverse)],
+  },
+
   proxy_reverse_list_pasv => {
     order => ++$order,
     test_class => [qw(forking reverse)],
@@ -3011,6 +3016,121 @@ EOC
   unlink($log_file);
 }
 
+sub proxy_reverse_abort {
+  my $self = shift;
+  my $tmpdir = $self->{tmpdir};
+  my $setup = test_setup($tmpdir, 'proxy');
+
+  my $vhost_port = ProFTPD::TestSuite::Utils::get_high_numbered_port();
+  $vhost_port += 12;
+
+  my $proxy_config = get_reverse_proxy_config($tmpdir, $setup->{log_file},
+    $vhost_port);
+
+  my $config = {
+    PidFile => $setup->{pid_file},
+    ScoreboardFile => $setup->{scoreboard_file},
+    SystemLog => $setup->{log_file},
+    TraceLog => $setup->{log_file},
+    Trace => 'DEFAULT:10 event:0 lock:0 scoreboard:0 signal:0 proxy:20 proxy.ftp.conn:20 proxy.ftp.ctrl:20 proxy.ftp.data:20 proxy.ftp.msg:20',
+
+    AuthUserFile => $setup->{auth_user_file},
+    AuthGroupFile => $setup->{auth_group_file},
+    SocketBindTight => 'on',
+
+    IfModules => {
+      'mod_proxy.c' => $proxy_config,
+
+      'mod_delay.c' => {
+        DelayEngine => 'off',
+      },
+    },
+  };
+
+  my ($port, $config_user, $config_group) = config_write($setup->{config_file},
+    $config);
+
+  if (open(my $fh, ">> $setup->{config_file}")) {
+    print $fh <<EOC;
+<VirtualHost 127.0.0.1>
+  Port $vhost_port
+  ServerName "Real Server"
+
+  AuthUserFile $setup->{auth_user_file}
+  AuthGroupFile $setup->{auth_group_file}
+  AuthOrder mod_auth_file.c
+
+  AllowOverride off
+  WtmpLog off
+  TransferLog none
+</VirtualHost>
+EOC
+    unless (close($fh)) {
+      die("Can't write $setup->{config_file}: $!");
+    }
+
+  } else {
+    die("Can't open $setup->{config_file}: $!");
+  }
+
+  # Open pipes, for use between the parent and child processes.  Specifically,
+  # the child will indicate when it's done with its test by writing a message
+  # to the parent.
+  my ($rfh, $wfh);
+  unless (pipe($rfh, $wfh)) {
+    die("Can't open pipe: $!");
+  }
+
+  my $ex;
+
+  # Fork child
+  $self->handle_sigchld();
+  defined(my $pid = fork()) or die("Can't fork: $!");
+  if ($pid) {
+    eval {
+      sleep(1);
+
+      my $client = ProFTPD::TestSuite::FTP->new('127.0.0.1', $port, 0, 1);
+      $client->login($setup->{user}, $setup->{passwd});
+
+      $client->quote('ABOR');
+      my $resp_code = $client->response_code();
+      my $resp_msg = $client->response_msg();
+
+      my $expected = 226;
+      $self->assert($expected == $resp_code,
+        test_msg("Expected response code $expected, got $resp_code"));
+
+      $expected = 'Abort successful';
+      $self->assert($expected eq $resp_msg,
+        test_msg("Expected response message '$expected', got '$resp_msg'"));
+
+      $client->quit();
+    };
+    if ($@) {
+      $ex = $@;
+    }
+
+    $wfh->print("done\n");
+    $wfh->flush();
+
+  } else {
+    eval { server_wait($setup->{config_file}, $rfh) };
+    if ($@) {
+      warn($@);
+      exit 1;
+    }
+
+    exit 0;
+  }
+
+  # Stop server
+  server_stop($setup->{pid_file});
+  $self->assert_child_ok($pid);
+
+  test_cleanup($setup->{log_file}, $ex);
+}
+
 sub proxy_reverse_list_pasv {
   my $self = shift;
   my $tmpdir = $self->{tmpdir};
@@ -4966,38 +5086,7 @@ EOC
 sub proxy_reverse_retr_abort {
   my $self = shift;
   my $tmpdir = $self->{tmpdir};
-
-  my $config_file = "$tmpdir/proxy.conf";
-  my $pid_file = File::Spec->rel2abs("$tmpdir/proxy.pid");
-  my $scoreboard_file = File::Spec->rel2abs("$tmpdir/proxy.scoreboard");
-
-  my $log_file = test_get_logfile();
-
-  my $auth_user_file = File::Spec->rel2abs("$tmpdir/proxy.passwd");
-  my $auth_group_file = File::Spec->rel2abs("$tmpdir/proxy.group");
-
-  my $user = 'proftpd';
-  my $passwd = 'test';
-  my $group = 'ftpd';
-  my $home_dir = File::Spec->rel2abs($tmpdir);
-  my $uid = 500;
-  my $gid = 500;
-
-  # Make sure that, if we're running as root, that the home directory has
-  # permissions/privs set for the account we create
-  if ($< == 0) {
-    unless (chmod(0755, $home_dir)) {
-      die("Can't set perms on $home_dir to 0755: $!");
-    }
-
-    unless (chown($uid, $gid, $home_dir)) {
-      die("Can't set owner of $home_dir to $uid/$gid: $!");
-    }
-  }
-
-  auth_user_write($auth_user_file, $user, $passwd, $uid, $gid, $home_dir,
-    '/bin/bash');
-  auth_group_write($auth_group_file, $group, $gid, $user);
+  my $setup = test_setup($tmpdir, 'proxy');
 
   my $test_datalen = (4 * 1024 * 1024);
   my $test_file = File::Spec->rel2abs("$tmpdir/test.txt");
@@ -5015,22 +5104,23 @@ sub proxy_reverse_retr_abort {
   my $vhost_port = ProFTPD::TestSuite::Utils::get_high_numbered_port();
   $vhost_port += 12;
 
-  my $proxy_config = get_reverse_proxy_config($tmpdir, $log_file, $vhost_port);
-
+  my $proxy_config = get_reverse_proxy_config($tmpdir, $setup->{log_file},
+    $vhost_port);
   my $timeout_idle = 10;
 
   my $config = {
-    PidFile => $pid_file,
-    ScoreboardFile => $scoreboard_file,
-    SystemLog => $log_file,
-    TraceLog => $log_file,
+    PidFile => $setup->{pid_file},
+    ScoreboardFile => $setup->{scoreboard_file},
+    SystemLog => $setup->{log_file},
+    TraceLog => $setup->{log_file},
     Trace => 'DEFAULT:10 event:0 lock:0 scoreboard:0 signal:0 proxy:20 proxy.ftp.conn:20 proxy.ftp.ctrl:20 proxy.ftp.data:20 proxy.ftp.msg:20',
 
-    AuthUserFile => $auth_user_file,
-    AuthGroupFile => $auth_group_file,
+    AuthUserFile => $setup->{auth_user_file},
+    AuthGroupFile => $setup->{auth_group_file},
     SocketBindTight => 'on',
     TimeoutIdle => $timeout_idle,
-    UseIPv6 => 'on',
+    TimeoutLinger => 1,
+    UseIPv6 => 'off',
 
     IfModules => {
       'mod_proxy.c' => $proxy_config,
@@ -5042,37 +5132,38 @@ sub proxy_reverse_retr_abort {
 
     Limit => {
       LOGIN => {
-        DenyUser => $user,
+        DenyUser => $setup->{user},
       },
     },
-
   };
 
-  my ($port, $config_user, $config_group) = config_write($config_file, $config);
+  my ($port, $config_user, $config_group) = config_write($setup->{config_file},
+    $config);
 
-  if (open(my $fh, ">> $config_file")) {
+  if (open(my $fh, ">> $setup->{config_file}")) {
     print $fh <<EOC;
 <VirtualHost 127.0.0.1>
   Port $vhost_port
   ServerName "Real Server"
 
-  AuthUserFile $auth_user_file
-  AuthGroupFile $auth_group_file
+  AuthUserFile $setup->{auth_user_file}
+  AuthGroupFile $setup->{auth_group_file}
   AuthOrder mod_auth_file.c
 
   AllowOverride off
   TimeoutIdle $timeout_idle
+  TimeoutLinger 1
 
   TransferLog none
   WtmpLog off
 </VirtualHost>
 EOC
     unless (close($fh)) {
-      die("Can't write $config_file: $!");
+      die("Can't write $setup->{config_file}: $!");
     }
 
   } else {
-    die("Can't open $config_file: $!");
+    die("Can't open $setup->{config_file}: $!");
   }
 
   # Open pipes, for use between the parent and child processes.  Specifically,
@@ -5091,8 +5182,9 @@ EOC
   if ($pid) {
     eval {
       sleep(1);
+
       my $client = ProFTPD::TestSuite::FTP->new('127.0.0.1', $port, 0, 1);
-      $client->login($user, $passwd);
+      $client->login($setup->{user}, $setup->{passwd});
       $client->type('binary');
 
       my $conn = $client->retr_raw($test_file);
@@ -5103,7 +5195,7 @@ EOC
 
       my $buf;
       $conn->read($buf, 8192, 30);
-      eval { $conn->close() };
+      eval { $client->quote('ABOR') };
 
       my $resp_code = $client->response_code();
       my $resp_msg = $client->response_msg();
@@ -5111,7 +5203,6 @@ EOC
 
       $client->quit();
     };
-
     if ($@) {
       $ex = $@;
     }
@@ -5120,7 +5211,7 @@ EOC
     $wfh->flush();
 
   } else {
-    eval { server_wait($config_file, $rfh, $timeout_idle + 2) };
+    eval { server_wait($setup->{config_file}, $rfh, $timeout_idle + 2) };
     if ($@) {
       warn($@);
       exit 1;
@@ -5130,18 +5221,10 @@ EOC
   }
 
   # Stop server
-  server_stop($pid_file);
-
+  server_stop($setup->{pid_file});
   $self->assert_child_ok($pid);
 
-  if ($ex) {
-    test_append_logfile($log_file, $ex);
-    unlink($log_file);
-
-    die($ex);
-  }
-
-  unlink($log_file);
+  test_cleanup($setup->{log_file}, $ex);
 }
 
 sub proxy_reverse_stor_pasv {
@@ -6230,38 +6313,7 @@ EOC
 sub proxy_reverse_stor_abort {
   my $self = shift;
   my $tmpdir = $self->{tmpdir};
-
-  my $config_file = "$tmpdir/proxy.conf";
-  my $pid_file = File::Spec->rel2abs("$tmpdir/proxy.pid");
-  my $scoreboard_file = File::Spec->rel2abs("$tmpdir/proxy.scoreboard");
-
-  my $log_file = test_get_logfile();
-
-  my $auth_user_file = File::Spec->rel2abs("$tmpdir/proxy.passwd");
-  my $auth_group_file = File::Spec->rel2abs("$tmpdir/proxy.group");
-
-  my $user = 'proftpd';
-  my $passwd = 'test';
-  my $group = 'ftpd';
-  my $home_dir = File::Spec->rel2abs($tmpdir);
-  my $uid = 500;
-  my $gid = 500;
-
-  # Make sure that, if we're running as root, that the home directory has
-  # permissions/privs set for the account we create
-  if ($< == 0) {
-    unless (chmod(0755, $home_dir)) {
-      die("Can't set perms on $home_dir to 0755: $!");
-    }
-
-    unless (chown($uid, $gid, $home_dir)) {
-      die("Can't set owner of $home_dir to $uid/$gid: $!");
-    }
-  }
-
-  auth_user_write($auth_user_file, $user, $passwd, $uid, $gid, $home_dir,
-    '/bin/bash');
-  auth_group_write($auth_group_file, $group, $gid, $user);
+  my $setup = test_setup($tmpdir, 'proxy');
 
   my $test_datalen = (4 * 1024 * 1024);
   my $test_file = File::Spec->rel2abs("$tmpdir/test.txt");
@@ -6269,22 +6321,24 @@ sub proxy_reverse_stor_abort {
   my $vhost_port = ProFTPD::TestSuite::Utils::get_high_numbered_port();
   $vhost_port += 12;
 
-  my $proxy_config = get_reverse_proxy_config($tmpdir, $log_file, $vhost_port);
+  my $proxy_config = get_reverse_proxy_config($tmpdir, $setup->{log_file},
+    $vhost_port);
 
   my $timeout_idle = 10;
 
   my $config = {
-    PidFile => $pid_file,
-    ScoreboardFile => $scoreboard_file,
-    SystemLog => $log_file,
-    TraceLog => $log_file,
+    PidFile => $setup->{pid_file},
+    ScoreboardFile => $setup->{scoreboard_file},
+    SystemLog => $setup->{log_file},
+    TraceLog => $setup->{log_file},
     Trace => 'DEFAULT:10 event:0 lock:0 scoreboard:0 signal:0 proxy:20 proxy.ftp.conn:20 proxy.ftp.ctrl:20 proxy.ftp.data:20 proxy.ftp.msg:20',
 
-    AuthUserFile => $auth_user_file,
-    AuthGroupFile => $auth_group_file,
+    AuthUserFile => $setup->{auth_user_file},
+    AuthGroupFile => $setup->{auth_group_file},
     SocketBindTight => 'on',
     TimeoutIdle => $timeout_idle,
-    UseIPv6 => 'on',
+    TimeoutLinger => 1,
+    UseIPv6 => 'off',
 
     IfModules => {
       'mod_proxy.c' => $proxy_config,
@@ -6296,37 +6350,37 @@ sub proxy_reverse_stor_abort {
 
     Limit => {
       LOGIN => {
-        DenyUser => $user,
+        DenyUser => $setup->{user},
       },
     },
-
   };
 
-  my ($port, $config_user, $config_group) = config_write($config_file, $config);
+  my ($port, $config_user, $config_group) = config_write($setup->{config_file},
+    $config);
 
-  if (open(my $fh, ">> $config_file")) {
+  if (open(my $fh, ">> $setup->{config_file}")) {
     print $fh <<EOC;
 <VirtualHost 127.0.0.1>
   Port $vhost_port
   ServerName "Real Server"
 
-  AuthUserFile $auth_user_file
-  AuthGroupFile $auth_group_file
+  AuthUserFile $setup->{auth_user_file}
+  AuthGroupFile $setup->{auth_group_file}
   AuthOrder mod_auth_file.c
 
   AllowOverride off
   TimeoutIdle $timeout_idle
-
+  TimeoutLinger 1
   TransferLog none
   WtmpLog off
 </VirtualHost>
 EOC
     unless (close($fh)) {
-      die("Can't write $config_file: $!");
+      die("Can't write $setup->{config_file}: $!");
     }
 
   } else {
-    die("Can't open $config_file: $!");
+    die("Can't open $setup->{config_file}: $!");
   }
 
   # Open pipes, for use between the parent and child processes.  Specifically,
@@ -6345,8 +6399,9 @@ EOC
   if ($pid) {
     eval {
       sleep(1);
+
       my $client = ProFTPD::TestSuite::FTP->new('127.0.0.1', $port, 0, 1);
-      $client->login($user, $passwd);
+      $client->login($setup->{user}, $setup->{passwd});
       $client->type('binary');
 
       my $conn = $client->stor_raw($test_file);
@@ -6365,7 +6420,6 @@ EOC
 
       $client->quit();
     };
-
     if ($@) {
       $ex = $@;
     }
@@ -6374,7 +6428,7 @@ EOC
     $wfh->flush();
 
   } else {
-    eval { server_wait($config_file, $rfh, $timeout_idle + 2) };
+    eval { server_wait($setup->{config_file}, $rfh, $timeout_idle + 2) };
     if ($@) {
       warn($@);
       exit 1;
@@ -6384,18 +6438,10 @@ EOC
   }
 
   # Stop server
-  server_stop($pid_file);
-
+  server_stop($setup->{pid_file});
   $self->assert_child_ok($pid);
 
-  if ($ex) {
-    test_append_logfile($log_file, $ex);
-    unlink($log_file);
-
-    die($ex);
-  }
-
-  unlink($log_file);
+  test_cleanup($setup->{log_file}, $ex);
 }
 
 sub proxy_reverse_rest_retr {
diff --git a/t/lib/ProFTPD/Tests/Modules/mod_proxy/tls.pm b/t/lib/ProFTPD/Tests/Modules/mod_proxy/tls.pm
index 2c48da1..fdeaccf 100644
--- a/t/lib/ProFTPD/Tests/Modules/mod_proxy/tls.pm
+++ b/t/lib/ProFTPD/Tests/Modules/mod_proxy/tls.pm
@@ -100,6 +100,11 @@ my $TESTS = {
     test_class => [qw(forking mod_tls reverse)],
   },
 
+  proxy_reverse_frontend_backend_tls_abort => {
+    order => ++$order,
+    test_class => [qw(forking mod_tls reverse)],
+  },
+
   proxy_reverse_frontend_tls_json_peruser => {
     order => ++$order,
     test_class => [qw(forking mod_tls reverse)],
@@ -3323,6 +3328,186 @@ EOC
   unlink($log_file);
 }
 
+sub proxy_reverse_frontend_backend_tls_abort {
+  my $self = shift;
+  my $tmpdir = $self->{tmpdir};
+  my $setup = test_setup($tmpdir, 'proxy');
+
+  my $cert_file = File::Spec->rel2abs('t/etc/modules/mod_tls/server-cert.pem');
+  my $ca_file = File::Spec->rel2abs('t/etc/modules/mod_tls/ca-cert.pem');
+
+  my $vhost_port = ProFTPD::TestSuite::Utils::get_high_numbered_port();
+  $vhost_port += 12;
+
+  my $proxy_config = get_reverse_proxy_config($tmpdir, $setup->{log_file},
+    $vhost_port);
+  $proxy_config->{ProxyTLSEngine} = 'auto';
+  $proxy_config->{ProxyTLSCACertificateFile} = $ca_file;
+  $proxy_config->{ProxyTLSVerifyServer} = 'off';
+
+  if ($ENV{TEST_VERBOSE}) {
+    $proxy_config->{ProxyTLSOptions} = 'EnableDiags';
+  }
+
+  my $config = {
+    PidFile => $setup->{pid_file},
+    ScoreboardFile => $setup->{scoreboard_file},
+    SystemLog => $setup->{log_file},
+    TraceLog => $setup->{log_file},
+    Trace => 'DEFAULT:10 event:0 lock:0 netio:20 scoreboard:0 signal:0 proxy:20 proxy.netio:20 proxy.db:20 proxy.reverse:20 proxy.tls:20 proxy.ftp.conn:20 proxy.ftp.ctrl:20 proxy.ftp.data:20 proxy.ftp.msg:20 proxy.ftp.sess:20 tls:20',
+
+    AuthUserFile => $setup->{auth_user_file},
+    AuthGroupFile => $setup->{auth_group_file},
+    SocketBindTight => 'on',
+
+    IfModules => {
+      'mod_proxy.c' => $proxy_config,
+
+      'mod_tls.c' => {
+        TLSEngine => 'on',
+        TLSLog => $setup->{log_file},
+        TLSProtocol => 'SSLv3 TLSv1',
+        TLSRequired => 'on',
+        TLSRSACertificateFile => $cert_file,
+        TLSCACertificateFile => $ca_file,
+        TLSOptions => 'NoSessionReuseRequired EnableDiags',
+        TLSTimeoutHandshake => 5,
+        TLSVerifyClient => 'off',
+        TLSVerifyServer => 'off',
+      },
+
+      'mod_delay.c' => {
+        DelayEngine => 'off',
+      },
+    },
+
+    Limit => {
+      LOGIN => {
+        DenyUser => $setup->{user},
+      },
+    },
+  };
+
+  my ($port, $config_user, $config_group) = config_write($setup->{config_file},
+    $config);
+
+  if (open(my $fh, ">> $setup->{config_file}")) {
+    print $fh <<EOC;
+<VirtualHost 127.0.0.1>
+  Port $vhost_port
+  ServerName "Real Server"
+
+  AuthUserFile $setup->{auth_user_file}
+  AuthGroupFile $setup->{auth_group_file}
+  AuthOrder mod_auth_file.c
+
+  AllowOverride off
+  WtmpLog off
+  TransferLog none
+
+  <IfModule mod_tls.c>
+    TLSEngine on
+    TLSLog $setup->{log_file}
+    TLSProtocol SSLv3 TLSv1
+    TLSRequired on
+    TLSRSACertificateFile $cert_file
+    TLSCACertificateFile $ca_file
+
+    TLSVerifyClient off
+    TLSVerifyServer off
+    TLSOptions EnableDiags NoSessionReuseRequired
+  </IfModule>
+</VirtualHost>
+EOC
+    unless (close($fh)) {
+      die("Can't write $setup->{config_file}: $!");
+    }
+
+  } else {
+    die("Can't open $setup->{config_file}: $!");
+  }
+
+  require Net::FTPSSL;
+
+  # Open pipes, for use between the parent and child processes.  Specifically,
+  # the child will indicate when it's done with its test by writing a message
+  # to the parent.
+  my ($rfh, $wfh);
+  unless (pipe($rfh, $wfh)) {
+    die("Can't open pipe: $!");
+  }
+
+  my $ex;
+
+  # Fork child
+  $self->handle_sigchld();
+  defined(my $pid = fork()) or die("Can't fork: $!");
+  if ($pid) {
+    eval {
+      # Give the server a chance to start up
+      sleep(2);
+
+      my $ssl_opts = {
+        SSL_verify_mode => $IO::Socket::SSL::SSL_VERIFY_NONE,
+      };
+
+      my $client_opts = {
+        Encryption => 'E',
+        Port => $port,
+        SSL_Client_Certificate => $ssl_opts,
+      };
+
+      if ($ENV{TEST_VERBOSE}) {
+        $client_opts->{Debug} = 1;
+      }
+
+      my $client = Net::FTPSSL->new('127.0.0.1', %$client_opts);
+
+      unless ($client) {
+        die("Can't connect to FTPS server: " . IO::Socket::SSL::errstr());
+      }
+
+      unless ($client->login($setup->{user}, $setup->{passwd})) {
+        die("Can't login: " . $client->last_message());
+      }
+
+      my $res = $client->_abort();
+      unless ($res) {
+        die("ABOR failed unexpectedly: " . $client->last_message() .
+          "(" . IO::Socket::SSL::errstr() . ")");
+      }
+
+      my $resp_msg = $client->last_message();
+      my $expected = '226 Abort successful';
+      $self->assert($expected eq $resp_msg,
+        test_msg("Expected response '$expected', got '$resp_msg'"));
+
+      $client->quit();
+    };
+    if ($@) {
+      $ex = $@;
+    }
+
+    $wfh->print("done\n");
+    $wfh->flush();
+
+  } else {
+    eval { server_wait($setup->{config_file}, $rfh, 20) };
+    if ($@) {
+      warn($@);
+      exit 1;
+    }
+
+    exit 0;
+  }
+
+  # Stop server
+  server_stop($setup->{pid_file});
+  $self->assert_child_ok($pid);
+
+  test_cleanup($setup->{log_file}, $ex);
+}
+
 sub proxy_reverse_frontend_tls_json_peruser {
   my $self = shift;
   my $tmpdir = $self->{tmpdir};