diff --git a/doc/release-notes.md b/doc/release-notes.md
index a29094b51..51da82d34 100644
--- a/doc/release-notes.md
+++ b/doc/release-notes.md
@@ -4,3 +4,15 @@ release-notes at release time)
 Notable changes
 ===============
 
+Fixed
+-----
+
+This is a hotfix release that fixes a regression in memory usage during
+Initial Block Download. The regression was indirectly caused by a change
+to prioritize downloading headers (PR #6231), introduced in release 5.3.1.
+It caused memory usage for new nodes to spike to roughly 11 GiB about an
+hour after starting Initial Block Download.
+
+The issue fixed by this release does not affect nodes that start from
+a fully synced chain, or that had sufficient memory available to get
+past the memory usage spike.