diff --git a/src/audio/copier/copier.c b/src/audio/copier/copier.c
index 93e018408bf3..2e3cbcfaac30 100644
--- a/src/audio/copier/copier.c
+++ b/src/audio/copier/copier.c
@@ -147,6 +147,16 @@ __cold static int copier_init(struct processing_module *mod)
 		cfg_total_size += gtw_cfg_var_size;
 	}
 
+	/*
+	 * gtw_cfg.config_length is host-controlled; make sure the resulting
+	 * copy length does not read past the init payload in the mailbox.
+	 */
+	if (md->cfg.size && cfg_total_size > md->cfg.size) {
+		comp_err(dev, "copier_init(): cfg size %zu exceeds init payload %zu",
+			 cfg_total_size, md->cfg.size);
+		return -EINVAL;
+	}
+
 	cd = mod_zalloc(mod, sizeof(*cd) + gtw_cfg_var_size);
 	if (!cd)
 		return -ENOMEM;
@@ -785,9 +795,11 @@ __cold static int set_attenuation(struct comp_dev *dev, uint32_t data_offset, co
 
 	assert_can_be_cold();
 
-	/* only support attenuation in format of 32bit */
-	if (data_offset > sizeof(uint32_t)) {
-		comp_err(dev, "attenuation data size %d is incorrect", data_offset);
+	/* only support attenuation in format of 32bit; the payload is
+	 * dereferenced as a uint32_t below so it must be exactly that size
+	 */
+	if (data_offset != sizeof(uint32_t)) {
+		comp_err(dev, "attenuation data size %u is incorrect", data_offset);
 		return -EINVAL;
 	}
 
diff --git a/src/audio/copier/copier_dai.c b/src/audio/copier/copier_dai.c
index dfd2590c7108..eaf178f255a3 100644
--- a/src/audio/copier/copier_dai.c
+++ b/src/audio/copier/copier_dai.c
@@ -88,6 +88,16 @@ static int copier_alh_assign_dai_index(struct comp_dev *dev,
 	switch (dai->type) {
 	case SOF_DAI_INTEL_HDA:
 		/* We use DAI_INTEL_HDA for ACE 2.0 platforms */
+		/*
+		 * alh_cfg.count is host-controlled and scales the config size
+		 * and mapping[] walk below; bound it before any arithmetic so a
+		 * crafted blob cannot read past the gateway config.
+		 */
+		if (alh_blob->alh_cfg.count > IPC4_ALH_MAX_NUMBER_OF_GTW) {
+			comp_err(mod->dev, "Invalid ALH count: %u",
+				 alh_blob->alh_cfg.count);
+			return -EINVAL;
+		}
 		alh_cfg_size = get_alh_config_size(alh_blob);
 		dma_config = (uint8_t *)gtw_cfg_data + alh_cfg_size;
 		dma_config_length = (cd->config.gtw_cfg.config_length << 2) - alh_cfg_size;
diff --git a/src/audio/copier/copier_generic.c b/src/audio/copier/copier_generic.c
index 89805f25af0c..bb5918819e5b 100644
--- a/src/audio/copier/copier_generic.c
+++ b/src/audio/copier/copier_generic.c
@@ -330,6 +330,12 @@ void copier_update_params(struct copier_data *cd, struct comp_dev *dev,
 		int j;
 		j = IPC4_SRC_QUEUE_ID(buf_get_id(sink));
 
+		/* src_queue id is host-controlled; bound it before indexing out_fmt[] */
+		if (j >= IPC4_COPIER_MODULE_OUTPUT_PINS_COUNT) {
+			comp_err(dev, "invalid src_queue id %d", j);
+			continue;
+		}
+
 		ipc4_update_buffer_format(sink, &cd->out_fmt[j]);
 	}
 
diff --git a/src/audio/copier/copier_ipcgtw.c b/src/audio/copier/copier_ipcgtw.c
index ed365c1e50d8..3efda681768a 100644
--- a/src/audio/copier/copier_ipcgtw.c
+++ b/src/audio/copier/copier_ipcgtw.c
@@ -223,6 +223,20 @@ __cold int copier_ipcgtw_create(struct processing_module *mod,
 		return -EINVAL;
 	}
 
+	/* config_length is in dwords; require enough dwords to cover the
+	 * gateway config header and the blob read below. Compare dword counts
+	 * (rather than scaling config_length by 4) so a large host-supplied
+	 * value cannot overflow the multiplication on 32-bit size_t.
+	 */
+	if (gtw_cfg->config_length <
+	    (sizeof(struct ipc4_gateway_config_data) +
+	     sizeof(struct ipc4_ipc_gateway_config_blob) +
+	     sizeof(uint32_t) - 1) / sizeof(uint32_t)) {
+		comp_err(dev, "ipc4_gateway_config_data too small: %u",
+			 gtw_cfg->config_length);
+		return -EINVAL;
+	}
+
 	cd->ipc_gtw = true;
 
 	/* The IPC gateway is treated as a host gateway */