diff --git a/ChangeLog.d/fix-secure-element-key-creation.txt b/ChangeLog.d/fix-secure-element-key-creation.txt
new file mode 100644
index 0000000..23a46c0
--- /dev/null
+++ b/ChangeLog.d/fix-secure-element-key-creation.txt
@@ -0,0 +1,5 @@
+Bugfix
+   * Fix error handling when creating a key in a dynamic secure element
+     (feature enabled by MBEDTLS_PSA_CRYPTO_SE_C). In a low memory condition,
+     the creation could return PSA_SUCCESS but using or destroying the key
+     would not work. Fixes #8537.
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index e85e579..46e1b37 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -1831,6 +1831,9 @@
 
         status = psa_copy_key_material_into_slot(
             slot, (uint8_t *) (&slot_number), sizeof(slot_number));
+        if (status != PSA_SUCCESS) {
+            return status;
+        }
     }
 
     if (*p_drv == NULL && method == PSA_KEY_CREATION_REGISTER) {
diff --git a/programs/ssl/ssl_mail_client.c b/programs/ssl/ssl_mail_client.c
index 31da2ed..f2e30e4 100644
--- a/programs/ssl/ssl_mail_client.c
+++ b/programs/ssl/ssl_mail_client.c
@@ -723,7 +723,11 @@
     mbedtls_printf("  > Write MAIL FROM to server:");
     fflush(stdout);
 
-    len = sprintf((char *) buf, "MAIL FROM:<%s>\r\n", opt.mail_from);
+    len = mbedtls_snprintf((char *) buf, sizeof(buf), "MAIL FROM:<%s>\r\n", opt.mail_from);
+    if (len < 0 || (size_t) len >= sizeof(buf)) {
+        mbedtls_printf(" failed\n  ! mbedtls_snprintf encountered error or truncated output\n\n");
+        goto exit;
+    }
     ret = write_ssl_and_get_response(&ssl, buf, len);
     if (ret < 200 || ret > 299) {
         mbedtls_printf(" failed\n  ! server responded with %d\n\n", ret);
@@ -735,7 +739,11 @@
     mbedtls_printf("  > Write RCPT TO to server:");
     fflush(stdout);
 
-    len = sprintf((char *) buf, "RCPT TO:<%s>\r\n", opt.mail_to);
+    len = mbedtls_snprintf((char *) buf, sizeof(buf), "RCPT TO:<%s>\r\n", opt.mail_to);
+    if (len < 0 || (size_t) len >= sizeof(buf)) {
+        mbedtls_printf(" failed\n  ! mbedtls_snprintf encountered error or truncated output\n\n");
+        goto exit;
+    }
     ret = write_ssl_and_get_response(&ssl, buf, len);
     if (ret < 200 || ret > 299) {
         mbedtls_printf(" failed\n  ! server responded with %d\n\n", ret);
@@ -759,11 +767,16 @@
     mbedtls_printf("  > Write content to server:");
     fflush(stdout);
 
-    len = sprintf((char *) buf, "From: %s\r\nSubject: Mbed TLS Test mail\r\n\r\n"
-                                "This is a simple test mail from the "
-                                "Mbed TLS mail client example.\r\n"
-                                "\r\n"
-                                "Enjoy!", opt.mail_from);
+    len = mbedtls_snprintf((char *) buf, sizeof(buf),
+                           "From: %s\r\nSubject: Mbed TLS Test mail\r\n\r\n"
+                           "This is a simple test mail from the "
+                           "Mbed TLS mail client example.\r\n"
+                           "\r\n"
+                           "Enjoy!", opt.mail_from);
+    if (len < 0 || (size_t) len >= sizeof(buf)) {
+        mbedtls_printf(" failed\n  ! mbedtls_snprintf encountered error or truncated output\n\n");
+        goto exit;
+    }
     ret = write_ssl_data(&ssl, buf, len);
 
     len = sprintf((char *) buf, "\r\n.\r\n");