diff --git a/src/util/auth.cpp b/src/util/auth.cpp
index 040d15bf9..5116e4be7 100644
--- a/src/util/auth.cpp
+++ b/src/util/auth.cpp
@@ -67,9 +67,9 @@ void generate_srp_verifier_and_salt(const std::string &name,
 	std::string *salt)
 {
 	char *bytes_v = nullptr;
-	size_t verifier_len;
+	size_t verifier_len = 0;
 	char *salt_ptr = nullptr;
-	size_t salt_len;
+	size_t salt_len = 0;
 	gen_srp_v(name, password, &salt_ptr, &salt_len, &bytes_v, &verifier_len);
 	*verifier = std::string(bytes_v, verifier_len);
 	*salt = std::string(salt_ptr, salt_len);