diff --git a/src/utils/cryptopro.c b/src/utils/cryptopro.c
index 099fbd1..3192fcc 100644
--- a/src/utils/cryptopro.c
+++ b/src/utils/cryptopro.c
@@ -391,6 +391,7 @@ get_verify_error(char** verify_error)
     if (n < 0 || (size_t)n >= size) {
         LOG_ERROR("get_verify_error failed. Error occurred in concatenation err_string");
         free(*verify_error);
+        *verify_error = NULL;
         return;
     }