diff --git a/ChangeLog b/ChangeLog
index 228a29c..1dad1af 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2022-02-01  Alex Kotov  <kotovalexarian@gmail.com>
+
+	* src/printf.c: Fix potential buffer overflow
+
 2022-01-24  Alex Kotov  <kotovalexarian@gmail.com>
 
 	* include/kernaux/ntoa.h: Add func "kernaux_itoa"
diff --git a/src/printf.c b/src/printf.c
index 9e3b8f5..6c5b374 100644
--- a/src/printf.c
+++ b/src/printf.c
@@ -576,6 +576,7 @@ size_t _ntoa_long_long(out_fct_type out, char* buffer, size_t idx, size_t maxlen
  * Idea: superleaf1995
  * Implementation: smwmaster
  */
+static const size_t map_size = 630;
 static const char *const map =
     "\xD3\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9"
     "\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xD3\xF9\xF9"
@@ -611,15 +612,11 @@ static const char *const map =
     "\xF7\xF9\xF9\xD3\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9"
     "\xF9\xF9\xF9\xF9\xF5\xB2\x96\xE9\xE9\x96\xA1\xBD\xF5\xF9\xF9\xF9\xF9\xF9"
     "\xD3\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9"
-    "\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xD3\xD3\xD9"
-    "\xD9\xD9\xC1\x04&&i\x05&&i\x05&&\xC9\x04&&i\x05&&i\x05&&i\x05&&i\x05&&i"
-    "\x05&&i\x05&&i\x05&&\xD1\x04&&i\x05&&\xD9\x04&&i\x05&&i\x05&&)\x05&&\xFB"
-    "\x06&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05"
-    "&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&-\x05&&"
-    "\xD1\x06&&-\x05&&\xCA\x04&&-\x05&&";
+    "\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xF9\xD3\xD3\xD9";
 
 char _custom(const unsigned int flags, size_t *const index)
 {
+    if (*index >= map_size) return '\0';
     return map[(*index)++] ^ (73 + ((flags >> 8) | 128));
 }
 #endif // ENABLE_BLOAT