diff --git a/src/tls.c b/src/tls.c
index 976150ef8..94bda4772 100644
--- a/src/tls.c
+++ b/src/tls.c
@@ -16567,15 +16567,18 @@ int TLSX_Parse(WOLFSSL* ssl, const byte* input, word16 length, byte msgType,
      * contain SupportedGroups and vice-versa. */
     if (IsAtLeastTLSv1_3(ssl->version) && msgType == client_hello && isRequest) {
         int hasKeyShare = !IS_OFF(seenType, TLSX_ToSemaphore(TLSX_KEY_SHARE));
-        int hasSupportedGroups = !IS_OFF(seenType, TLSX_ToSemaphore(TLSX_SUPPORTED_GROUPS));
+        int hasSupportedGroups = !IS_OFF(seenType,
+            TLSX_ToSemaphore(TLSX_SUPPORTED_GROUPS));
 
         if (hasKeyShare && !hasSupportedGroups) {
-            WOLFSSL_MSG("ClientHello with KeyShare extension missing required SupportedGroups extension");
-            return MISSING_HANDSHAKE_DATA;
+            WOLFSSL_MSG("ClientHello with KeyShare extension missing required "
+                        "SupportedGroups extension");
+            return INCOMPLETE_DATA;
         }
         if (hasSupportedGroups && !hasKeyShare) {
-            WOLFSSL_MSG("ClientHello with SupportedGroups extension missing required KeyShare extension");
-            return MISSING_HANDSHAKE_DATA;
+            WOLFSSL_MSG("ClientHello with SupportedGroups extension missing "
+                        "required KeyShare extension");
+            return INCOMPLETE_DATA;
         }
     }
 #endif
diff --git a/tests/api/test_tls13.c b/tests/api/test_tls13.c
index 9c4823ccb..0ad54951e 100644
--- a/tests/api/test_tls13.c
+++ b/tests/api/test_tls13.c
@@ -2318,3 +2318,168 @@ int test_tls13_hrr_different_cs(void)
 #endif
     return EXPECT_RESULT();
 }
+
+#if defined(WOLFSSL_TLS13) && !defined(NO_WOLFSSL_SERVER) && \
+    defined(HAVE_ECC)
+/* Called when writing. */
+static int MESend(WOLFSSL* ssl, char* buf, int sz, void* ctx)
+{
+    (void)ssl;
+    (void)buf;
+    (void)sz;
+    (void)ctx;
+
+    /* Force error return from wolfSSL_accept_TLSv13(). */
+    return WANT_WRITE;
+}
+/* Called when reading. */
+static int MERecv(WOLFSSL* ssl, char* buf, int sz, void* ctx)
+{
+    WOLFSSL_BUFFER_INFO* msg = (WOLFSSL_BUFFER_INFO*)ctx;
+    int len = (int)msg->length;
+
+    (void)ssl;
+    (void)sz;
+
+    /* Pass back as much of message as will fit in buffer. */
+    if (len > sz)
+        len = sz;
+    XMEMCPY(buf, msg->buffer, len);
+    /* Move over returned data. */
+    msg->buffer += len;
+    msg->length -= len;
+
+    /* Amount actually copied. */
+    return len;
+}
+#endif
+
+int test_tls13_sg_missing(void)
+{
+    EXPECT_DECLS;
+#if defined(WOLFSSL_TLS13) && !defined(NO_WOLFSSL_SERVER) && \
+    defined(HAVE_ECC)
+    WOLFSSL_CTX *ctx = NULL;
+    WOLFSSL *ssl = NULL;
+    byte clientHello[] = {
+        0x16, 0x03, 0x03, 0x00, 0xcb, 0x01, 0x00, 0x00,
+        0xc7, 0x03, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01,
+        0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+        0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+        0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+        0x01, 0x01, 0x01, 0x20, 0x03, 0x03, 0x03, 0x03,
+        0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+        0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+        0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+        0x03, 0x03, 0x03, 0x03, 0x00, 0x02, 0x13, 0x01,
+        0x01, 0x00, 0x00, 0x7c, 0x00, 0x0d, 0x00, 0x06,
+        0x00, 0x04, 0x04, 0x01, 0x08, 0x04,
+                                            /* KeyShare */
+                                            0x00, 0x33,
+        0x00, 0x67, 0x00, 0x65, 0x00, 0x18, 0x00, 0x61,
+        0x04, 0x53, 0x3e, 0xe5, 0xbf, 0x40, 0xec, 0x2d,
+        0x67, 0x98, 0x8b, 0x77, 0xf3, 0x17, 0x48, 0x9b,
+        0xb6, 0xdf, 0x95, 0x29, 0x25, 0xc7, 0x09, 0xfc,
+        0x03, 0x81, 0x11, 0x1a, 0x59, 0x56, 0xf2, 0xd7,
+        0x58, 0x11, 0x0e, 0x59, 0xd3, 0xd7, 0xc1, 0x72,
+        0x9e, 0x2c, 0x0d, 0x70, 0xea, 0xf7, 0x73, 0xe6,
+        0x12, 0x01, 0x16, 0x42, 0x6d, 0xe2, 0x43, 0x6a,
+        0x2f, 0x5f, 0xdd, 0x7f, 0xe5, 0x4f, 0xaf, 0x95,
+        0x2b, 0x04, 0xfd, 0x13, 0xf5, 0x16, 0xce, 0x62,
+        0x7f, 0x89, 0xd2, 0x01, 0x9d, 0x4c, 0x87, 0x96,
+        0x95, 0x9e, 0x43, 0x33, 0xc7, 0x06, 0x5b, 0x49,
+        0x6c, 0xa6, 0x34, 0xd5, 0xdc, 0x63, 0xbd, 0xe9,
+        0x1f,
+              /* SupportedVersions */
+              0x00, 0x2b, 0x00, 0x03, 0x02, 0x03, 0x04
+        /* Missing SupportedGroups. */
+    };
+    WOLFSSL_BUFFER_INFO msg;
+    WOLFSSL_ALERT_HISTORY h;
+
+    /* Set up wolfSSL context. */
+    ExpectNotNull(ctx = wolfSSL_CTX_new(wolfTLSv1_3_server_method()));
+    ExpectTrue(wolfSSL_CTX_use_certificate_file(ctx, eccCertFile,
+        CERT_FILETYPE));
+    ExpectTrue(wolfSSL_CTX_use_PrivateKey_file(ctx, eccKeyFile,
+        CERT_FILETYPE));
+    /* Read from 'msg'. */
+    wolfSSL_SetIORecv(ctx, MERecv);
+    /* No where to send to - dummy sender. */
+    wolfSSL_SetIOSend(ctx, MESend);
+
+    /* Test cipher suite list with many copies of a cipher suite. */
+    ExpectNotNull(ssl = wolfSSL_new(ctx));
+    msg.buffer = clientHello;
+    msg.length = (unsigned int)sizeof(clientHello);
+    wolfSSL_SetIOReadCtx(ssl, &msg);
+
+    ExpectIntEQ(wolfSSL_accept_TLSv13(ssl),
+        WC_NO_ERR_TRACE(WOLFSSL_FATAL_ERROR));
+    ExpectIntEQ(wolfSSL_get_alert_history(ssl, &h), WOLFSSL_SUCCESS);
+    ExpectIntEQ(h.last_tx.code, missing_extension);
+    ExpectIntEQ(h.last_tx.level, alert_fatal);
+    wolfSSL_free(ssl);
+    wolfSSL_CTX_free(ctx);
+#endif
+    return EXPECT_RESULT();
+}
+
+int test_tls13_ks_missing(void)
+{
+    EXPECT_DECLS;
+#if defined(WOLFSSL_TLS13) && !defined(NO_WOLFSSL_SERVER) && \
+    defined(HAVE_ECC)
+    WOLFSSL_CTX *ctx = NULL;
+    WOLFSSL *ssl = NULL;
+    byte clientHello[] = {
+        0x16, 0x03, 0x03, 0x00, 0x66, 0x01, 0x00, 0x00,
+        0x62, 0x03, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01,
+        0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+        0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+        0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+        0x01, 0x01, 0x01, 0x20, 0x03, 0x03, 0x03, 0x03,
+        0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+        0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+        0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03,
+        0x03, 0x03, 0x03, 0x03, 0x00, 0x02, 0x13, 0x01,
+        0x01, 0x00, 0x00, 0x17, 0x00, 0x0d, 0x00, 0x06,
+        0x00, 0x04, 0x04, 0x01, 0x08, 0x04,
+                                            /* SupportedGroups */
+                                            0x00, 0x0a,
+        0x00, 0x02, 0x00, 0x18,
+                                /* SupportedVersions */
+                                0x00, 0x2b, 0x00, 0x03,
+        0x02, 0x03, 0x04
+        /* Missing KeyShare. */
+    };
+    WOLFSSL_BUFFER_INFO msg;
+    WOLFSSL_ALERT_HISTORY h;
+
+    /* Set up wolfSSL context. */
+    ExpectNotNull(ctx = wolfSSL_CTX_new(wolfTLSv1_3_server_method()));
+    ExpectTrue(wolfSSL_CTX_use_certificate_file(ctx, eccCertFile,
+        CERT_FILETYPE));
+    ExpectTrue(wolfSSL_CTX_use_PrivateKey_file(ctx, eccKeyFile,
+        CERT_FILETYPE));
+    /* Read from 'msg'. */
+    wolfSSL_SetIORecv(ctx, MERecv);
+    /* No where to send to - dummy sender. */
+    wolfSSL_SetIOSend(ctx, MESend);
+
+    /* Test cipher suite list with many copies of a cipher suite. */
+    ExpectNotNull(ssl = wolfSSL_new(ctx));
+    msg.buffer = clientHello;
+    msg.length = (unsigned int)sizeof(clientHello);
+    wolfSSL_SetIOReadCtx(ssl, &msg);
+
+    ExpectIntEQ(wolfSSL_accept_TLSv13(ssl),
+        WC_NO_ERR_TRACE(WOLFSSL_FATAL_ERROR));
+    ExpectIntEQ(wolfSSL_get_alert_history(ssl, &h), WOLFSSL_SUCCESS);
+    ExpectIntEQ(h.last_tx.code, missing_extension);
+    ExpectIntEQ(h.last_tx.level, alert_fatal);
+    wolfSSL_free(ssl);
+    wolfSSL_CTX_free(ctx);
+#endif
+    return EXPECT_RESULT();
+}
diff --git a/tests/api/test_tls13.h b/tests/api/test_tls13.h
index 42a19073b..e6bdcd00e 100644
--- a/tests/api/test_tls13.h
+++ b/tests/api/test_tls13.h
@@ -32,6 +32,8 @@ int test_tls13_pq_groups(void);
 int test_tls13_early_data(void);
 int test_tls13_same_ch(void);
 int test_tls13_hrr_different_cs(void);
+int test_tls13_sg_missing(void);
+int test_tls13_ks_missing(void);
 
 #define TEST_TLS13_DECLS                                   \
     TEST_DECL_GROUP("tls13", test_tls13_apis),             \
@@ -41,6 +43,8 @@ int test_tls13_hrr_different_cs(void);
     TEST_DECL_GROUP("tls13", test_tls13_pq_groups),        \
     TEST_DECL_GROUP("tls13", test_tls13_early_data),       \
     TEST_DECL_GROUP("tls13", test_tls13_same_ch),          \
-    TEST_DECL_GROUP("tls13", test_tls13_hrr_different_cs)
+    TEST_DECL_GROUP("tls13", test_tls13_hrr_different_cs), \
+    TEST_DECL_GROUP("tls13", test_tls13_sg_missing),       \
+    TEST_DECL_GROUP("tls13", test_tls13_ks_missing)
 
 #endif /* WOLFCRYPT_TEST_TLS13_H */