diff --git a/ArduCopter/ReleaseNotes.txt b/ArduCopter/ReleaseNotes.txt
index 363f2affc2..faf5e4df70 100644
--- a/ArduCopter/ReleaseNotes.txt
+++ b/ArduCopter/ReleaseNotes.txt
@@ -1,5 +1,16 @@
 ArduPilot Copter Release Notes:
 -------------------------------
+
+Release 4.5.1 8th April 2024
+
+This release fixes a critical bug in the CRSF R/C protocol parser that
+can lead to a handfault and a vehicle crashing. A similar fix was
+applied to the GHST protocol, although we believe that GHST could not
+be affected by the bug, so this was just a precaution.
+
+There are no other changes in this release.
+
+------------------------------------------------------------------
 Release 4.5.0 2nd April 2024
 
 No changes from 4.5.0-beta4