diff --git a/doc/nrf/releases_and_maturity/releases/release-notes-changelog.rst b/doc/nrf/releases_and_maturity/releases/release-notes-changelog.rst
index 2c192ea98aa2..2bd9297887a4 100644
--- a/doc/nrf/releases_and_maturity/releases/release-notes-changelog.rst
+++ b/doc/nrf/releases_and_maturity/releases/release-notes-changelog.rst
@@ -162,7 +162,7 @@ Thread
 Zigbee
 ------
 
-|no_changes_yet_note|
+* Fixed the :file:`zb_add_ota_header.py` script to allow a patch version higher than 9 in an ``APPLICATION_VERSION_STRING``.
 
 Wi-Fi
 -----
diff --git a/scripts/bootloader/zb_add_ota_header.py b/scripts/bootloader/zb_add_ota_header.py
index 542240c2c335..846fceabd66b 100644
--- a/scripts/bootloader/zb_add_ota_header.py
+++ b/scripts/bootloader/zb_add_ota_header.py
@@ -141,7 +141,7 @@ def __add_optional_fields(self, fields_length, field_control_bit_mask, fields_fo
 
 def convert_version_string_to_int(s):
     """Convert from semver string "1.2.3", to integer 1020003"""
-    match = re.match(r'^([0-9]+)\.([0-9]+)\.([0-9])(?:\+[0-9]+)?$', s)
+    match = re.match(r'^([0-9]+)\.([0-9]+)\.([0-9]+)(?:\+[0-9]+)?$', s)
     if match is None:
         raise ValueError('application-version-string parameter must be on the format x.y.z or x.y.z+t')
     js = [0x100*0x10000, 0x10000, 1]