diff --git a/components/bt/esp_ble_iso/host/iso/iso.c b/components/bt/esp_ble_iso/host/iso/iso.c
index 9516cccf2f1..35e33e0361f 100644
--- a/components/bt/esp_ble_iso/host/iso/iso.c
+++ b/components/bt/esp_ble_iso/host/iso/iso.c
@@ -1656,10 +1656,27 @@ static bool is_advanced_cig_param(const struct bt_iso_cig_param *param)
         return true;
     }
 
+    /* This probe runs before valid_cig_param(); guard structure here so
+     * caller misuse (NULL cis_channels/cis/qos, or an over-reported num_cis)
+     * falls through to that check's -EINVAL instead of a NULL or
+     * out-of-bounds deref in this probe.
+     */
+    if (param->cis_channels == NULL ||
+            param->num_cis > BT_ISO_MAX_GROUP_ISO_COUNT ||
+            param->num_cis > CONFIG_BT_ISO_MAX_CHAN) {
+        return false;
+    }
+
     /* Check if any of the CIS contain any test-param-only values */
     for (uint8_t i = 0U; i < param->num_cis; i++) {
         const struct bt_iso_chan *cis = param->cis_channels[i];
-        const struct bt_iso_chan_qos *qos = cis->qos;
+        const struct bt_iso_chan_qos *qos;
+
+        if (cis == NULL || cis->qos == NULL) {
+            continue;
+        }
+
+        qos = cis->qos;
 
         if (qos->num_subevents > 0U) {
             return true;
@@ -1785,6 +1802,14 @@ static bool valid_cig_param(const struct bt_iso_cig_param *param, bool advanced,
         return false;
     }
 
+    /* Not guaranteed by all callers (bt_iso_cig_reconfigure does not pre-check
+     * it); the per-CIS loop below dereferences cis_channels[i] directly.
+     */
+    if (param->cis_channels == NULL) {
+        LOG_ERR("CisChansNull");
+        return false;
+    }
+
     if (param->num_cis > BT_ISO_MAX_GROUP_ISO_COUNT ||
             param->num_cis > CONFIG_BT_ISO_MAX_CHAN) {
         LOG_ERR("TooLargeNumCis[%u][%u]",
@@ -2659,17 +2684,32 @@ static bool is_advanced_big_param(const struct bt_iso_big_create_param *param)
         return true;
     }
 
+    /* This probe runs before valid_big_param(); guard structure here so
+     * caller misuse (NULL bis_channels/bis/qos/qos->tx, or an over-reported
+     * num_bis) falls through to that check's -EINVAL instead of a NULL or
+     * out-of-bounds deref in this probe.
+     */
+    if (param->bis_channels == NULL ||
+            param->num_bis > BT_ISO_MAX_GROUP_ISO_COUNT ||
+            param->num_bis > CONFIG_BT_ISO_MAX_CHAN) {
+        return false;
+    }
+
     /* Check if any of the CIS contain any test-param-only values */
     for (uint8_t i = 0U; i < param->num_bis; i++) {
         const struct bt_iso_chan *bis = param->bis_channels[i];
-        const struct bt_iso_chan_qos *qos = bis->qos;
+        const struct bt_iso_chan_qos *qos;
+
+        if (bis == NULL || bis->qos == NULL || bis->qos->tx == NULL) {
+            continue;
+        }
+
+        qos = bis->qos;
 
         if (qos->num_subevents > 0U) {
             return true;
         }
 
-        assert(qos->tx != NULL && "BigWithNullTx");
-
         if (qos->tx->max_pdu > 0U || qos->tx->burst_number > 0U) {
             return true;
         }
@@ -2693,6 +2733,17 @@ static bool valid_big_param(const struct bt_iso_big_create_param *param, bool ad
         return false;
     }
 
+    /* Bound num_bis before the per-BIS loop so a caller that over-reports it
+     * cannot drive the loop past the bis_channels[] array.
+     */
+    CHECKIF(param->num_bis > BT_ISO_MAX_GROUP_ISO_COUNT ||
+            param->num_bis > CONFIG_BT_ISO_MAX_CHAN) {
+        LOG_ERR("TooLargeNumBis[%u][%u][%u]",
+                param->num_bis, BT_ISO_MAX_GROUP_ISO_COUNT, CONFIG_BT_ISO_MAX_CHAN);
+
+        return false;
+    }
+
     for (uint8_t i = 0; i < param->num_bis; i++) {
         struct bt_iso_chan *bis = param->bis_channels[i];
 
@@ -2736,14 +2787,6 @@ static bool valid_big_param(const struct bt_iso_big_create_param *param, bool ad
         return false;
     }
 
-    CHECKIF(param->num_bis > BT_ISO_MAX_GROUP_ISO_COUNT ||
-            param->num_bis > CONFIG_BT_ISO_MAX_CHAN) {
-        LOG_ERR("TooLargeNumBis[%u][%u]",
-                param->num_bis, MAX(CONFIG_BT_ISO_MAX_CHAN, BT_ISO_MAX_GROUP_ISO_COUNT));
-
-        return false;
-    }
-
     CHECKIF(!IN_RANGE(param->interval, BT_ISO_SDU_INTERVAL_MIN, BT_ISO_SDU_INTERVAL_MAX)) {
         LOG_ERR("InvInterval[%u]", param->interval);