diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 46ade67b9..77ad75547 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -782,7 +782,7 @@ struct mbedtls_ssl_transform
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     uint8_t in_cid_len;
     uint8_t out_cid_len;
-    unsigned char in_cid [ MBEDTLS_SSL_CID_OUT_LEN_MAX ];
+    unsigned char in_cid [ MBEDTLS_SSL_CID_IN_LEN_MAX ];
     unsigned char out_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ];
 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */