diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index b07d07ab1a..0d54ae9b0b 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -6376,6 +6376,7 @@ static uint16_t ssl_preset_default_sig_algs[] = {
 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
     MBEDTLS_TLS13_SIG_RSA_PSS_RSAE_SHA256,
 #endif
+    MBEDTLS_TLS13_SIG_RSA_PKCS1_SHA256,
 
     MBEDTLS_TLS13_SIG_NONE
 };
@@ -6395,6 +6396,7 @@ static uint16_t ssl_preset_suiteb_sig_algs[] = {
 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
     MBEDTLS_TLS13_SIG_RSA_PSS_RSAE_SHA256,
 #endif
+    MBEDTLS_TLS13_SIG_RSA_PKCS1_SHA256,
 
     MBEDTLS_TLS13_SIG_NONE
 };
diff --git a/library/ssl_tls13_generic.c b/library/ssl_tls13_generic.c
index 2dd5c50313..d5a67a922c 100644
--- a/library/ssl_tls13_generic.c
+++ b/library/ssl_tls13_generic.c
@@ -376,11 +376,16 @@ static int ssl_tls13_parse_certificate_verify( mbedtls_ssl_context *ssl,
             break;
 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
         case MBEDTLS_TLS13_SIG_RSA_PSS_RSAE_SHA256:
-            MBEDTLS_SSL_DEBUG_MSG( 4, ( "Certificate Verify: using RSA" ) );
+            MBEDTLS_SSL_DEBUG_MSG( 4, ( "Certificate Verify: using RSA PSS" ) );
             md_alg = MBEDTLS_MD_SHA256;
             sig_alg = MBEDTLS_PK_RSASSA_PSS;
             break;
 #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
+        case MBEDTLS_TLS13_SIG_RSA_PKCS1_SHA256:
+            MBEDTLS_SSL_DEBUG_MSG( 4, ( "Certificate Verify: using RSA PKCS1 V1.5" ) );
+            md_alg = MBEDTLS_MD_SHA256;
+            sig_alg = MBEDTLS_PK_RSA;
+            break;
         default:
             MBEDTLS_SSL_DEBUG_MSG( 1, ( "Certificate Verify: Unknown signature algorithm." ) );
             goto error;
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index d43d66260e..c5f693035a 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -8907,6 +8907,44 @@ run_test    "TLS 1.3 m->G AES_128_GCM_SHA256      , RSA_PSS_RSAE_SHA256" \
             -c "mbedtls_ssl_tls13_process_certificate_verify() returned 0" \
             -c "HTTP/1.0 200 OK"
 
+requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL
+requires_config_enabled MBEDTLS_DEBUG_C
+requires_config_enabled MBEDTLS_SSL_CLI_C
+requires_config_enabled MBEDTLS_X509_RSASSA_PSS_SUPPORT
+requires_gnutls_next
+run_test    "TLS 1.3 m->G AES_128_GCM_SHA256      , RSA_PKCSV15_SHA256" \
+            "$G_NEXT_SRV_RSA --disable-client-cert --priority=NORMAL:+CIPHER-ALL:+SHA256:+GROUP-SECP256R1:+ECDHE-ECDSA:+AEAD:+SIGN-RSA-SHA256:-VERS-ALL:+VERS-TLS1.3:%NO_TICKETS:%DISABLE_TLS13_COMPAT_MODE" \
+            "$P_CLI debug_level=4 force_version=tls1_3 server_name=localhost force_ciphersuite=TLS1-3-AES-128-GCM-SHA256" \
+            0 \
+            -c "tls1_3 client state: 0"     \
+            -c "tls1_3 client state: 2"     \
+            -c "tls1_3 client state: 19"    \
+            -c "tls1_3 client state: 5"     \
+            -c "tls1_3 client state: 3"     \
+            -c "tls1_3 client state: 9"     \
+            -c "tls1_3 client state: 13"    \
+            -c "tls1_3 client state: 11"    \
+            -c "tls1_3 client state: 14"    \
+            -c "tls1_3 client state: 15"    \
+            -c "<= ssl_tls1_3_process_server_hello" \
+            -c "server hello, chosen ciphersuite: ( 1301 ) - TLS1-3-AES-128-GCM-SHA256" \
+            -s "Ephemeral EC Diffie-Hellman parameters" \
+            -s "Version: TLS1.3" \
+            -s "Cipher: AES-128-GCM" \
+            -S "Client Signature:" \
+            -s "Server Signature: RSA-PSS-RSAE-SHA256" \
+            -c "ECDH curve: x25519"         \
+            -c "server hello, chosen ciphersuite: ( 1301 ) - TLS1-3-AES-128-GCM-SHA256" \
+            -c "Certificate Verify: Signature algorithm ( 0804 )" \
+            -c "=> ssl_tls1_3_process_server_hello" \
+            -c "<= parse encrypted extensions"      \
+            -c "Certificate verification flags clear" \
+            -c "=> parse certificate verify"          \
+            -c "<= parse certificate verify"          \
+            -c "mbedtls_ssl_tls13_process_certificate_verify() returned 0" \
+            -c "<= parse finished message" \
+            -c "HTTP/1.0 200 OK"
+
 # Test heap memory usage after handshake
 requires_config_enabled MBEDTLS_MEMORY_DEBUG
 requires_config_enabled MBEDTLS_MEMORY_BUFFER_ALLOC_C