diff --git a/doc/Changelog b/doc/Changelog
index cda8f1df6..c72a255bf 100644
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -16,6 +16,8 @@
 	  reported by X41 D-Sec.
 	- Fix Local Memory Leak in cachedb_init(),
 	  reported by X41 D-Sec.
+	- Fix Integer Underflow in Regional Allocator,
+	  reported by X41 D-Sec.
 
 19 November 2019: Wouter
 	- Fix CVE-2019-18934, shell execution in ipsecmod.
diff --git a/util/regional.c b/util/regional.c
index 5be09eb46..ff36d0e21 100644
--- a/util/regional.c
+++ b/util/regional.c
@@ -84,6 +84,7 @@ struct regional*
 regional_create_custom(size_t size)
 {
 	struct regional* r = (struct regional*)malloc(size);
+	size = ALIGN_UP(size, ALIGNMENT);
 	log_assert(sizeof(struct regional) <= size);
 	if(!r) return NULL;
 	r->first_size = size;