diff --git a/src/handle_query_contract_ui.c b/src/handle_query_contract_ui.c
index afeb662..c485565 100644
--- a/src/handle_query_contract_ui.c
+++ b/src/handle_query_contract_ui.c
@@ -7,7 +7,7 @@ static void prepend_ticker(char *dest, size_t destsize, const char *ticker) {
         THROW(0x6503);
     }
     size_t ticker_len = strnlen(ticker, MAX_TICKER_LEN);
-    size_t dest_len = strnlen(dest, destsize - ticker_len);
+    size_t dest_len = strnlen(dest, destsize);
 
     if (dest_len + ticker_len >= destsize) {
         THROW(0x6503);
diff --git a/tests/elfs/paraswap_nanos.elf b/tests/elfs/paraswap_nanos.elf
index 66a9167..724ace1 100755
Binary files a/tests/elfs/paraswap_nanos.elf and b/tests/elfs/paraswap_nanos.elf differ
diff --git a/tests/elfs/paraswap_nanox.elf b/tests/elfs/paraswap_nanox.elf
index 715811c..6365254 100755
Binary files a/tests/elfs/paraswap_nanox.elf and b/tests/elfs/paraswap_nanox.elf differ