diff --git a/features/mbedtls/targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F439xI/mbedtls_device.h b/features/mbedtls/targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F439xI/mbedtls_device.h
index 90213bea118..dfbc82055ef 100644
--- a/features/mbedtls/targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F439xI/mbedtls_device.h
+++ b/features/mbedtls/targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F439xI/mbedtls_device.h
@@ -20,9 +20,7 @@
 #ifndef MBEDTLS_DEVICE_H
 #define MBEDTLS_DEVICE_H
 
-/* FIXME: Don't enable AES hardware acceleration until issue #4928 is fixed.
- * (https://github.com/ARMmbed/mbed-os/issues/4928) */
-/* #define MBEDTLS_AES_ALT */
+#define MBEDTLS_AES_ALT
 
 #define MBEDTLS_SHA256_ALT
 
diff --git a/features/mbedtls/targets/TARGET_STM/aes_alt.c b/features/mbedtls/targets/TARGET_STM/aes_alt.c
index 8736d7ee474..15e57eb095e 100644
--- a/features/mbedtls/targets/TARGET_STM/aes_alt.c
+++ b/features/mbedtls/targets/TARGET_STM/aes_alt.c
@@ -1,5 +1,5 @@
 /*
- *  Hardware aes collector for the STM32F4 family
+ *  Hardware aes implementation for STM32F4 STM32F7 and STM32L4 families
  *******************************************************************************
  * Copyright (c) 2017, STMicroelectronics
  *  SPDX-License-Identifier: Apache-2.0
@@ -129,15 +129,18 @@ int mbedtls_aes_crypt_ecb( mbedtls_aes_context *ctx,
 
     /* allow multi-instance of CRYP use: restore context for CRYP hw module */
     ctx->hcryp_aes.Instance->CR = ctx->ctx_save_cr;
+    ctx->hcryp_aes.Phase = HAL_CRYP_PHASE_READY;
+    ctx->hcryp_aes.Init.DataType = CRYP_DATATYPE_8B;
+    ctx->hcryp_aes.Init.pKey = ctx->aes_key;
 
     if(mode == MBEDTLS_AES_DECRYPT) { /* AES decryption */
-        ctx->hcryp_aes.Init.DataType = CRYP_DATATYPE_8B;
-        ctx->hcryp_aes.Init.pKey = ctx->aes_key;
-        mbedtls_aes_decrypt( ctx, input, output );
+        if (mbedtls_internal_aes_decrypt( ctx, input, output )){
+            return ST_ERR_AES_BUSY;
+        }
     } else { /* AES encryption */
-        ctx->hcryp_aes.Init.DataType = CRYP_DATATYPE_8B;
-        ctx->hcryp_aes.Init.pKey = ctx->aes_key;
-        mbedtls_aes_encrypt( ctx, input, output );
+        if (mbedtls_internal_aes_encrypt( ctx, input, output )) {
+            return ST_ERR_AES_BUSY;
+        }
     }
     /* allow multi-instance of CRYP use: save context for CRYP HW module CR */
     ctx->ctx_save_cr = ctx->hcryp_aes.Instance->CR;
@@ -147,29 +150,50 @@ int mbedtls_aes_crypt_ecb( mbedtls_aes_context *ctx,
 
 #if defined(MBEDTLS_CIPHER_MODE_CBC)
 #if defined (TARGET_STM32L486xG)
+static int st_cbc_restore_context(mbedtls_aes_context *ctx){
+    uint32_t tickstart;
+    tickstart = HAL_GetTick();
+    while((ctx->hcryp_aes.Instance->SR & AES_SR_BUSY) != 0){
+        if ((HAL_GetTick() - tickstart) > ST_AES_TIMEOUT) {
+            return ST_ERR_AES_BUSY; // timeout: CRYP processor is busy
+        }
+    }
+    /* allow multi-instance of CRYP use: restore context for CRYP hw module */
+    ctx->hcryp_aes.Instance->CR = ctx->ctx_save_cr;
+    return 0;
+}
+
 static int st_hal_cryp_cbc( mbedtls_aes_context *ctx, uint32_t opmode, size_t length, 
                             unsigned char iv[16], uint8_t *input, uint8_t *output) 
 {
-    int status = 0;
     ctx->hcryp_aes.Init.pInitVect = &iv[0]; // used in process, not in the init
-    if ((ctx->hcryp_aes.Init.OperatingMode != opmode) || \
-         (ctx->hcryp_aes.Init.ChainingMode != CRYP_CHAINMODE_AES_CBC) || \
-         (ctx->hcryp_aes.Init.KeyWriteFlag != CRYP_KEY_WRITE_ENABLE)) {
-
-        /* Re-initialize AES IP with proper parameters */
-        if (HAL_CRYP_DeInit(&ctx->hcryp_aes) != HAL_OK)
-            return HAL_ERROR;
-        ctx->hcryp_aes.Init.OperatingMode = opmode;
-        ctx->hcryp_aes.Init.ChainingMode = CRYP_CHAINMODE_AES_CBC;
-        ctx->hcryp_aes.Init.KeyWriteFlag = CRYP_KEY_WRITE_ENABLE;
-        if (HAL_CRYP_Init(&ctx->hcryp_aes) != HAL_OK)
-            return HAL_ERROR;
-    }
-
-    status =  HAL_CRYPEx_AES(&ctx->hcryp_aes, input, length, output, 10);
+    /* At this moment only, we know we have CBC mode: Re-initialize AES
+        IP with proper parameters and apply key and IV for multi context usecase */
+    if (HAL_CRYP_DeInit(&ctx->hcryp_aes) != HAL_OK)
+        return ST_ERR_AES_BUSY;
+    ctx->hcryp_aes.Init.OperatingMode = opmode;
+    ctx->hcryp_aes.Init.ChainingMode = CRYP_CHAINMODE_AES_CBC;
+    ctx->hcryp_aes.Init.KeyWriteFlag = CRYP_KEY_WRITE_ENABLE;
+    if (HAL_CRYP_Init(&ctx->hcryp_aes) != HAL_OK)
+        return ST_ERR_AES_BUSY;
 
-    return status;
+    if(HAL_CRYPEx_AES(&ctx->hcryp_aes, input, length, output, 10) != 0)
+        return ST_ERR_AES_BUSY;
+    return 0;
+}
+#else /* STM32F4 and STM32F7 */
+static int st_cbc_restore_context(mbedtls_aes_context *ctx){
+    /* allow multi-instance of CRYP use: restore context for CRYP hw module */
+    ctx->hcryp_aes.Instance->CR = ctx->ctx_save_cr;
+    /* Re-initialize AES processor with proper parameters
+       and (re-)apply key and IV for multi context usecases */
+    if (HAL_CRYP_DeInit(&ctx->hcryp_aes) != HAL_OK)
+        return ST_ERR_AES_BUSY;
+    if (HAL_CRYP_Init(&ctx->hcryp_aes) != HAL_OK)
+        return ST_ERR_AES_BUSY;
+    return 0;
 }
+
 #endif /* TARGET_STM32L486xG */
 
 int mbedtls_aes_crypt_cbc( mbedtls_aes_context *ctx,
@@ -179,25 +203,66 @@ int mbedtls_aes_crypt_cbc( mbedtls_aes_context *ctx,
                     const unsigned char *input,
                     unsigned char *output )
 {
-    int status = 0;
+    uint32_t tickstart;
+    uint32_t *iv_ptr = (uint32_t *)&iv[0];
     if( length % 16 )
         return( MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH );
+    ctx->hcryp_aes.Init.pInitVect = &iv[0];
+    if (st_cbc_restore_context(ctx) != 0)
+        return (ST_ERR_AES_BUSY);
+
 #if defined (TARGET_STM32L486xG)
+
     if( mode == MBEDTLS_AES_DECRYPT ) {
-        status = st_hal_cryp_cbc(ctx, CRYP_ALGOMODE_KEYDERIVATION_DECRYPT, length, iv, (uint8_t *)input, (uint8_t *)output);
+        if (st_hal_cryp_cbc(ctx, CRYP_ALGOMODE_KEYDERIVATION_DECRYPT, length, iv, (uint8_t *)input, (uint8_t *)output) != 0)
+            return ST_ERR_AES_BUSY;
+        /* Save the internal IV vector for multi context purpose */
+        tickstart = HAL_GetTick();
+        while((ctx->hcryp_aes.Instance->SR & AES_SR_BUSY) != 0){
+            if ((HAL_GetTick() - tickstart) > ST_AES_TIMEOUT) {
+                return ST_ERR_AES_BUSY; // timeout: CRYP processor is busy
+            }
+        }
+        ctx->ctx_save_cr = ctx->hcryp_aes.Instance->CR; // save here before overwritten
+        ctx->hcryp_aes.Instance->CR &= ~AES_CR_EN;
+        *iv_ptr++ = ctx->hcryp_aes.Instance->IVR3;
+        *iv_ptr++ = ctx->hcryp_aes.Instance->IVR2;
+        *iv_ptr++ = ctx->hcryp_aes.Instance->IVR1;
+        *iv_ptr++ = ctx->hcryp_aes.Instance->IVR0;
     } else {
-        status = st_hal_cryp_cbc(ctx, CRYP_ALGOMODE_ENCRYPT, length, iv, (uint8_t *)input, (uint8_t *)output);
+        if (st_hal_cryp_cbc(ctx, CRYP_ALGOMODE_ENCRYPT, length, iv, (uint8_t *)input, (uint8_t *)output) != 0)
+            return ST_ERR_AES_BUSY;
+        memcpy( iv, output, 16 ); /* current output is the IV vector for the next call */
+        ctx->ctx_save_cr = ctx->hcryp_aes.Instance->CR;
     }
+
 #else
-    ctx->hcryp_aes.Init.pInitVect = &iv[0];
-    
+
     if( mode == MBEDTLS_AES_DECRYPT ) {
-        status = HAL_CRYP_AESCBC_Decrypt(&ctx->hcryp_aes, (uint8_t *)input, length, (uint8_t *)output, 10);
+        if (HAL_CRYP_AESCBC_Decrypt(&ctx->hcryp_aes, (uint8_t *)input, length, (uint8_t *)output, 10) != HAL_OK)
+            return ST_ERR_AES_BUSY;
+        /* Save the internal IV vector for multi context purpose */
+        tickstart = HAL_GetTick();
+        while((ctx->hcryp_aes.Instance->SR & (CRYP_SR_IFEM | CRYP_SR_OFNE | CRYP_SR_BUSY)) != CRYP_SR_IFEM){
+            if ((HAL_GetTick() - tickstart) > ST_AES_TIMEOUT) {
+                return ST_ERR_AES_BUSY; // timeout: CRYP processor is busy
+            }
+        }
+        ctx->ctx_save_cr = ctx->hcryp_aes.Instance->CR; // save here before overwritten
+        ctx->hcryp_aes.Instance->CR &= ~CRYP_CR_CRYPEN;
+        *iv_ptr++ = ctx->hcryp_aes.Instance->IV0LR;
+        *iv_ptr++ = ctx->hcryp_aes.Instance->IV0RR;
+        *iv_ptr++ = ctx->hcryp_aes.Instance->IV1LR;
+        *iv_ptr++ = ctx->hcryp_aes.Instance->IV1RR;
     } else {
-        status = HAL_CRYP_AESCBC_Encrypt(&ctx->hcryp_aes, (uint8_t *)input, length, (uint8_t *)output, 10);
+        if (HAL_CRYP_AESCBC_Encrypt(&ctx->hcryp_aes, (uint8_t *)input, length, (uint8_t *)output, 10) != HAL_OK)
+            return ST_ERR_AES_BUSY;
+        memcpy( iv, output, 16 ); /* current output is the IV vector for the next call */
+        ctx->ctx_save_cr = ctx->hcryp_aes.Instance->CR;
     }
+
 #endif
-    return( status );
+    return 0;
 }
 #endif /* MBEDTLS_CIPHER_MODE_CBC */
 
@@ -216,7 +281,8 @@ int mbedtls_aes_crypt_cfb128( mbedtls_aes_context *ctx,
     if( mode == MBEDTLS_AES_DECRYPT ) {
         while( length-- ) {
             if( n == 0 )
-                mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, iv, iv );
+                if (mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, iv, iv ) != 0)
+                    return ST_ERR_AES_BUSY;
 
             c = *input++;
             *output++ = (unsigned char)( c ^ iv[n] );
@@ -227,7 +293,8 @@ int mbedtls_aes_crypt_cfb128( mbedtls_aes_context *ctx,
     } else {
         while( length-- ) {
             if( n == 0 )
-                mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, iv, iv );
+                if (mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, iv, iv ) != 0)
+                    return ST_ERR_AES_BUSY;
 
             iv[n] = *output++ = (unsigned char)( iv[n] ^ *input++ );
 
@@ -253,7 +320,8 @@ int mbedtls_aes_crypt_cfb8( mbedtls_aes_context *ctx,
 
     while( length-- ) {
         memcpy( ov, iv, 16 );
-        mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, iv, iv );
+        if (mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, iv, iv ) != 0)
+            return ST_ERR_AES_BUSY;
 
         if( mode == MBEDTLS_AES_DECRYPT )
             ov[16] = *input;
@@ -286,7 +354,8 @@ int mbedtls_aes_crypt_ctr( mbedtls_aes_context *ctx,
     while( length-- )
     {
         if( n == 0 ) {
-            mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, nonce_counter, stream_block );
+            if (mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, nonce_counter, stream_block ) != 0)
+                return ST_ERR_AES_BUSY;
 
             for( i = 16; i > 0; i-- )
                 if( ++nonce_counter[i - 1] != 0 )
@@ -304,26 +373,42 @@ int mbedtls_aes_crypt_ctr( mbedtls_aes_context *ctx,
 }
 #endif /* MBEDTLS_CIPHER_MODE_CTR */
 
-void mbedtls_aes_encrypt( mbedtls_aes_context *ctx,
+int mbedtls_internal_aes_encrypt( mbedtls_aes_context *ctx,
                           const unsigned char input[16],
                           unsigned char output[16] )
 {
-    
-    if (HAL_CRYP_AESECB_Encrypt(&ctx->hcryp_aes, (uint8_t *)input, 16, (uint8_t *)output, 10) !=0) {
-        // error found to be returned
+    if (HAL_CRYP_AESECB_Encrypt(&ctx->hcryp_aes, (uint8_t *)input, 16, (uint8_t *)output, 10) != HAL_OK) {
+        // error found
+        return ST_ERR_AES_BUSY;
     }
+    return 0;
 
 }
 
-void mbedtls_aes_decrypt( mbedtls_aes_context *ctx,
-                          const unsigned char input[16],
-                          unsigned char output[16] )
+int mbedtls_internal_aes_decrypt( mbedtls_aes_context *ctx,
+                                  const unsigned char input[16],
+                                  unsigned char output[16] )
 {
-
-    if(HAL_CRYP_AESECB_Decrypt(&ctx->hcryp_aes, (uint8_t *)input, 16, (uint8_t *)output, 10)) {
-        // error found to be returned
+    if(HAL_CRYP_AESECB_Decrypt(&ctx->hcryp_aes, (uint8_t *)input, 16, (uint8_t *)output, 10) != HAL_OK) {
+        // error found
+        return ST_ERR_AES_BUSY;
     }
+    return 0;
 }
 
+#if !defined(MBEDTLS_DEPRECATED_REMOVED)
+void mbedtls_aes_encrypt( mbedtls_aes_context *ctx,
+                          const unsigned char input[16],
+                          unsigned char output[16] )
+{
+    mbedtls_internal_aes_encrypt( ctx, input, output );
+}
 
+void mbedtls_aes_decrypt( mbedtls_aes_context *ctx,
+                          const unsigned char input[16],
+                          unsigned char output[16] )
+{
+    mbedtls_internal_aes_decrypt( ctx, input, output );
+}
+#endif /* MBEDTLS_DEPRECATED_REMOVED */
 #endif /*MBEDTLS_AES_ALT*/
diff --git a/features/mbedtls/targets/TARGET_STM/aes_alt.h b/features/mbedtls/targets/TARGET_STM/aes_alt.h
index dbe4fdeec30..120c9af5f17 100644
--- a/features/mbedtls/targets/TARGET_STM/aes_alt.h
+++ b/features/mbedtls/targets/TARGET_STM/aes_alt.h
@@ -1,7 +1,7 @@
 /*
  *  aes_alt.h AES block cipher
  *******************************************************************************
- * Copyright (c) 2016, STMicroelectronics
+ * Copyright (c) 2017, STMicroelectronics
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -30,6 +30,9 @@
 #ifdef __cplusplus
 extern "C" {
 #endif
+
+#define ST_AES_TIMEOUT    ((uint32_t) 0xFF) /* 255 ms timeout for the crypto processor */
+#define ST_ERR_AES_BUSY   (-0x0023)      /* Crypto processor is busy, timeout occured */
 /**
  * \brief          AES context structure
  *
@@ -236,10 +239,12 @@ int mbedtls_aes_crypt_ctr( mbedtls_aes_context *ctx,
  * \param ctx       AES context
  * \param input     Plaintext block
  * \param output    Output (ciphertext) block
+ *
+ * \return          0 if successful
  */
-void mbedtls_aes_encrypt( mbedtls_aes_context *ctx,
-                          const unsigned char input[16],
-                          unsigned char output[16] );
+int mbedtls_internal_aes_encrypt( mbedtls_aes_context *ctx,
+                                  const unsigned char input[16],
+                                  unsigned char output[16] );
 
 /**
  * \brief           Internal AES block decryption function
@@ -249,10 +254,49 @@ void mbedtls_aes_encrypt( mbedtls_aes_context *ctx,
  * \param ctx       AES context
  * \param input     Ciphertext block
  * \param output    Output (plaintext) block
+ *
+ * \return          0 if successful
  */
-void mbedtls_aes_decrypt( mbedtls_aes_context *ctx,
-                          const unsigned char input[16],
-                          unsigned char output[16] );
+int mbedtls_internal_aes_decrypt( mbedtls_aes_context *ctx,
+                                  const unsigned char input[16],
+                                  unsigned char output[16] );
+
+#if !defined(MBEDTLS_DEPRECATED_REMOVED)
+#if defined(MBEDTLS_DEPRECATED_WARNING)
+#define MBEDTLS_DEPRECATED      __attribute__((deprecated))
+#else
+#define MBEDTLS_DEPRECATED
+#endif
+/**
+ * \brief           Deprecated internal AES block encryption function
+ *                  without return value.
+ *
+ * \deprecated      Superseded by mbedtls_aes_encrypt_ext() in 2.5.0
+ *
+ * \param ctx       AES context
+ * \param input     Plaintext block
+ * \param output    Output (ciphertext) block
+ */
+MBEDTLS_DEPRECATED void mbedtls_aes_encrypt( mbedtls_aes_context *ctx,
+                                             const unsigned char input[16],
+                                             unsigned char output[16] );
+
+/**
+ * \brief           Deprecated internal AES block decryption function
+ *                  without return value.
+ *
+ * \deprecated      Superseded by mbedtls_aes_decrypt_ext() in 2.5.0
+ *
+ * \param ctx       AES context
+ * \param input     Ciphertext block
+ * \param output    Output (plaintext) block
+ */
+MBEDTLS_DEPRECATED void mbedtls_aes_decrypt( mbedtls_aes_context *ctx,
+                                             const unsigned char input[16],
+                                             unsigned char output[16] );
+
+#undef MBEDTLS_DEPRECATED
+#endif /* !MBEDTLS_DEPRECATED_REMOVED */
 
 #ifdef __cplusplus
 }