diff --git a/wpa_supplicant/ChangeLog b/wpa_supplicant/ChangeLog
index c41d2e851..1f7d8d65a 100644
--- a/wpa_supplicant/ChangeLog
+++ b/wpa_supplicant/ChangeLog
@@ -8,6 +8,10 @@ ChangeLog for wpa_supplicant
 	* added a new network configuration option, wpa_ptk_rekey, that can be
 	  used to enforce frequent PTK rekeying, e.g., to mitigate some attacks
 	  against TKIP deficiencies
+	* added an optional mitigation mechanism for certain attacks against
+	  TKIP by delaying Michael MIC error reports by a random amount of time
+	  between 0 and 60 seconds; this can be enabled with a build option
+	  CONFIG_DELAYED_MIC_ERROR_REPORT=y in .config
 	* fixed EAP-AKA to use RES Length field in AT_RES as length in bits,
 	  not bytes
 
diff --git a/wpa_supplicant/Makefile b/wpa_supplicant/Makefile
index badda34da..277894c13 100644
--- a/wpa_supplicant/Makefile
+++ b/wpa_supplicant/Makefile
@@ -951,6 +951,10 @@ ifdef CONFIG_DEBUG_FILE
 CFLAGS += -DCONFIG_DEBUG_FILE
 endif
 
+ifdef CONFIG_DELAYED_MIC_ERROR_REPORT
+CFLAGS += -DCONFIG_DELAYED_MIC_ERROR_REPORT
+endif
+
 OBJS += ../src/drivers/scan_helpers.o
 
 OBJS_wpa_rm := ctrl_iface.o mlme.o ctrl_iface_unix.o
diff --git a/wpa_supplicant/defconfig b/wpa_supplicant/defconfig
index 38435cd10..2653654eb 100644
--- a/wpa_supplicant/defconfig
+++ b/wpa_supplicant/defconfig
@@ -364,3 +364,7 @@ CONFIG_PEERKEY=y
 
 # Enable privilege separation (see README 'Privilege separation' for details)
 #CONFIG_PRIVSEP=y
+
+# Enable mitigation against certain attacks against TKIP by delaying Michael
+# MIC error reports by a random amount of time between 0 and 60 seconds
+#CONFIG_DELAYED_MIC_ERROR_REPORT=y
diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c
index 45b5ac3a3..27dfd55ff 100644
--- a/wpa_supplicant/events.c
+++ b/wpa_supplicant/events.c
@@ -862,6 +862,22 @@ static void wpa_supplicant_event_disassoc(struct wpa_supplicant *wpa_s)
 }
 
 
+#ifdef CONFIG_DELAYED_MIC_ERROR_REPORT
+static void wpa_supplicant_delayed_mic_error_report(void *eloop_ctx,
+						    void *sock_ctx)
+{
+	struct wpa_supplicant *wpa_s = eloop_ctx;
+
+	if (!wpa_s->pending_mic_error_report)
+		return;
+
+	wpa_printf(MSG_DEBUG, "WPA: Sending pending MIC error report");
+	wpa_sm_key_request(wpa_s->wpa, 1, wpa_s->pending_mic_error_pairwise);
+	wpa_s->pending_mic_error_report = 0;
+}
+#endif /* CONFIG_DELAYED_MIC_ERROR_REPORT */
+
+
 static void
 wpa_supplicant_event_michael_mic_failure(struct wpa_supplicant *wpa_s,
 					 union wpa_event_data *data)
@@ -871,10 +887,25 @@ wpa_supplicant_event_michael_mic_failure(struct wpa_supplicant *wpa_s,
 
 	wpa_msg(wpa_s, MSG_WARNING, "Michael MIC failure detected");
 	pairwise = (data && data->michael_mic_failure.unicast);
-	wpa_sm_key_request(wpa_s->wpa, 1, pairwise);
 	os_get_time(&t);
-	if (wpa_s->last_michael_mic_error &&
-	    t.sec - wpa_s->last_michael_mic_error <= 60) {
+	if ((wpa_s->last_michael_mic_error &&
+	     t.sec - wpa_s->last_michael_mic_error <= 60) ||
+	    wpa_s->pending_mic_error_report) {
+		if (wpa_s->pending_mic_error_report) {
+			/*
+			 * Send the pending MIC error report immediately since
+			 * we are going to start countermeasures and AP better
+			 * do the same.
+			 */
+			wpa_sm_key_request(wpa_s->wpa, 1,
+					   wpa_s->pending_mic_error_pairwise);
+		}
+
+		/* Send the new MIC error report immediately since we are going
+		 * to start countermeasures and AP better do the same.
+		 */
+		wpa_sm_key_request(wpa_s->wpa, 1, pairwise);
+
 		/* initialize countermeasures */
 		wpa_s->countermeasures = 1;
 		wpa_msg(wpa_s, MSG_WARNING, "TKIP countermeasures started");
@@ -895,8 +926,46 @@ wpa_supplicant_event_michael_mic_failure(struct wpa_supplicant *wpa_s,
 				       wpa_s, NULL);
 		/* TODO: mark the AP rejected for 60 second. STA is
 		 * allowed to associate with another AP.. */
+	} else {
+#ifdef CONFIG_DELAYED_MIC_ERROR_REPORT
+		if (wpa_s->mic_errors_seen) {
+			/*
+			 * Reduce the effectiveness of Michael MIC error
+			 * reports as a means for attacking against TKIP if
+			 * more than one MIC failure is noticed with the same
+			 * PTK. We delay the transmission of the reports by a
+			 * random time between 0 and 60 seconds in order to
+			 * force the attacker wait 60 seconds before getting
+			 * the information on whether a frame resulted in a MIC
+			 * failure.
+			 */
+			u8 rval[4];
+			int sec;
+
+			if (os_get_random(rval, sizeof(rval)) < 0)
+				sec = os_random() % 60;
+			else
+				sec = WPA_GET_BE32(rval) % 60;
+			wpa_printf(MSG_DEBUG, "WPA: Delay MIC error report %d "
+				   "seconds", sec);
+			wpa_s->pending_mic_error_report = 1;
+			wpa_s->pending_mic_error_pairwise = pairwise;
+			eloop_cancel_timeout(
+				wpa_supplicant_delayed_mic_error_report,
+				wpa_s, NULL);
+			eloop_register_timeout(
+				sec, os_random() % 1000000,
+				wpa_supplicant_delayed_mic_error_report,
+				wpa_s, NULL);
+		} else {
+			wpa_sm_key_request(wpa_s->wpa, 1, pairwise);
+		}
+#else /* CONFIG_DELAYED_MIC_ERROR_REPORT */
+		wpa_sm_key_request(wpa_s->wpa, 1, pairwise);
+#endif /* CONFIG_DELAYED_MIC_ERROR_REPORT */
 	}
 	wpa_s->last_michael_mic_error = t.sec;
+	wpa_s->mic_errors_seen++;
 }
 
 
diff --git a/wpa_supplicant/wpa_supplicant_i.h b/wpa_supplicant/wpa_supplicant_i.h
index 9afae2a98..a8fb6d22b 100644
--- a/wpa_supplicant/wpa_supplicant_i.h
+++ b/wpa_supplicant/wpa_supplicant_i.h
@@ -334,6 +334,10 @@ struct wpa_supplicant {
 	struct wpa_client_mlme mlme;
 	int use_client_mlme;
 	int driver_4way_handshake;
+
+	int pending_mic_error_report;
+	int pending_mic_error_pairwise;
+	int mic_errors_seen; /* Michael MIC errors with the current PTK */
 };
 
 
diff --git a/wpa_supplicant/wpas_glue.c b/wpa_supplicant/wpas_glue.c
index d5e31ebb0..e1e2cd66e 100644
--- a/wpa_supplicant/wpas_glue.c
+++ b/wpa_supplicant/wpas_glue.c
@@ -427,11 +427,16 @@ static int wpa_supplicant_get_bssid(void *ctx, u8 *bssid)
 }
 
 
-static int wpa_supplicant_set_key(void *wpa_s, wpa_alg alg,
+static int wpa_supplicant_set_key(void *_wpa_s, wpa_alg alg,
 				  const u8 *addr, int key_idx, int set_tx,
 				  const u8 *seq, size_t seq_len,
 				  const u8 *key, size_t key_len)
 {
+	struct wpa_supplicant *wpa_s = _wpa_s;
+	if (alg == WPA_ALG_TKIP && key_idx == 0 && key_len == 32) {
+		/* Clear the MIC error counter when setting a new PTK. */
+		wpa_s->mic_errors_seen = 0;
+	}
 	return wpa_drv_set_key(wpa_s, alg, addr, key_idx, set_tx, seq, seq_len,
 			       key, key_len);
 }