diff --git a/components/mbedtls/test/test_mbedtls_mpi.c b/components/mbedtls/test/test_mbedtls_mpi.c
index 084fe34845..ed394e6bf4 100644
--- a/components/mbedtls/test/test_mbedtls_mpi.c
+++ b/components/mbedtls/test/test_mbedtls_mpi.c
@@ -18,7 +18,7 @@
 */
 void mbedtls_mpi_printf(const char *name, const mbedtls_mpi *X)
 {
-    static char buf[1024];
+    static char buf[2048];
     size_t n;
     memset(buf, 0, sizeof(buf));
     mbedtls_mpi_write_string(X, 16, buf, sizeof(buf)-1, &n);
@@ -29,11 +29,15 @@ void mbedtls_mpi_printf(const char *name, const mbedtls_mpi *X)
     }
 }
 
-/* Assert E = A * B */
-static void test_bignum_mult(const char *a_str, const char *b_str, const char *e_str, size_t mod_bits)
+/* 
+    Assert E == X, X=A*B if res_operands_overlap==0
+    Assert E == A, A=A*B if res_operands_overlap==1
+    Assert E == B, B=A*B if res_operands_overlap==2
+*/
+static void test_bignum_mult_variant(const char *a_str, const char *b_str, const char *e_str, size_t mod_bits, int res_operands_overlap)
 {
     mbedtls_mpi A, B, X, E, M;
-    char x_buf[1024] = { 0 };
+    char x_buf[2048] = {0};
     size_t x_buf_len = 0;
 
     mbedtls_mpi_init(&A);
@@ -44,9 +48,17 @@ static void test_bignum_mult(const char *a_str, const char *b_str, const char *e
     TEST_ASSERT_FALSE(mbedtls_mpi_read_string(&A, 16, a_str));
     TEST_ASSERT_FALSE(mbedtls_mpi_read_string(&B, 16, b_str));
 
-    /* E = A * B */
+    /* calulate X = A * B variant */
     TEST_ASSERT_FALSE(mbedtls_mpi_read_string(&E, 16, e_str));
-    TEST_ASSERT_FALSE(mbedtls_mpi_mul_mpi(&X, &A, &B));
+    if (res_operands_overlap == 0) {
+        TEST_ASSERT_FALSE(mbedtls_mpi_mul_mpi(&X, &A, &B));
+    } else if (res_operands_overlap == 1) {
+        mbedtls_mpi_copy( &X, &A );
+        TEST_ASSERT_FALSE(mbedtls_mpi_mul_mpi(&X, &X, &B));
+    } else if (res_operands_overlap == 2) {
+        mbedtls_mpi_copy( &X, &B );
+        TEST_ASSERT_FALSE(mbedtls_mpi_mul_mpi(&X, &A, &X));
+    }
 
     mbedtls_mpi_write_string(&X, 16, x_buf, sizeof(x_buf)-1, &x_buf_len);
     TEST_ASSERT_EQUAL_STRING_MESSAGE(e_str, x_buf, "mbedtls_mpi_mul_mpi result wrong");
@@ -73,6 +85,15 @@ static void test_bignum_mult(const char *a_str, const char *b_str, const char *e
     mbedtls_mpi_free(&E);
 }
 
+/* Assert E = A * B, including 3 variants: X=A*B A*=B, B*=A */
+static void test_bignum_mult(const char *a_str, const char *b_str, const char *e_str, size_t mod_bits)
+{
+    for (int overlap_operands=0; overlap_operands < 3; ++overlap_operands) {
+        test_bignum_mult_variant(a_str, b_str, e_str, mod_bits, overlap_operands);
+    }
+}
+
+
 TEST_CASE("test MPI multiplication", "[bignum]")
 {
     /* Run some trivial numbers tests w/ various high modulo bit counts,
@@ -115,6 +136,13 @@ TEST_CASE("test MPI multiplication", "[bignum]")
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
                      4096);
+
+    /* multiply two very large numbers (4080 bits x 4088 bits) with and without overlapping multipliers/multiplicant */
+    test_bignum_mult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
+                        0);
+
 }
 
 static bool test_bignum_modexp(const char *z_str, const char *x_str, const char *y_str, const char *m_str, int ret_error)