diff --git a/src/libstrongswan/plugins/gcrypt/gcrypt_rsa_private_key.c b/src/libstrongswan/plugins/gcrypt/gcrypt_rsa_private_key.c
index 5ef7daf61..c9526cac8 100644
--- a/src/libstrongswan/plugins/gcrypt/gcrypt_rsa_private_key.c
+++ b/src/libstrongswan/plugins/gcrypt/gcrypt_rsa_private_key.c
@@ -281,8 +281,8 @@ METHOD(private_key_t, decrypt, bool,
 	void *params, chunk_t encrypted, chunk_t *plain)
 {
 	gcry_error_t err;
-	gcry_sexp_t in, out;
-	chunk_t label = chunk_empty, decrypted;
+	gcry_sexp_t in, out = NULL;
+	chunk_t label = chunk_empty, decrypted = chunk_empty;
 	u_char *sexp;
 
 	switch (scheme)
diff --git a/src/libstrongswan/plugins/gcrypt/gcrypt_rsa_public_key.c b/src/libstrongswan/plugins/gcrypt/gcrypt_rsa_public_key.c
index 2200a2118..61e851498 100644
--- a/src/libstrongswan/plugins/gcrypt/gcrypt_rsa_public_key.c
+++ b/src/libstrongswan/plugins/gcrypt/gcrypt_rsa_public_key.c
@@ -240,7 +240,7 @@ METHOD(public_key_t, encrypt_, bool,
 	void *params, chunk_t plain, chunk_t *encrypted)
 {
 	gcry_error_t err;
-	gcry_sexp_t in, out;
+	gcry_sexp_t in, out = NULL;
 	chunk_t label = chunk_empty;
 	u_char *sexp;