diff --git a/chapter01/changelog.xml b/chapter01/changelog.xml
index edd7e524f..c4fd38872 100644
--- a/chapter01/changelog.xml
+++ b/chapter01/changelog.xml
@@ -45,6 +45,10 @@
     <listitem>
       <para>2021-07-20</para>
       <itemizedlist>
+        <listitem>
+          <para>[ken] - Update to linux-5.13.4 (security fix). Fixes
+          <ulink url="&lfs-ticket-root;4886">#4886</ulink>.</para>
+        </listitem>
         <listitem>
           <para>[xry111] - Use a fixed, non-zero UID for
           <systemitem class="username">tester</systemitem> user, and spawn a
diff --git a/packages.ent b/packages.ent
index 1606987cd..815d81a6e 100644
--- a/packages.ent
+++ b/packages.ent
@@ -425,12 +425,12 @@
 
 <!ENTITY linux-major-version "5">
 <!ENTITY linux-minor-version "13">
-<!ENTITY linux-patch-version "1">
+<!ENTITY linux-patch-version "4">
 <!--<!ENTITY linux-version "&linux-major-version;.&linux-minor-version;">-->
 <!ENTITY linux-version "&linux-major-version;.&linux-minor-version;.&linux-patch-version;">
-<!ENTITY linux-size "116,496 KB">
+<!ENTITY linux-size "116,536 KB">
 <!ENTITY linux-url "&kernel;linux/kernel/v&linux-major-version;.x/linux-&linux-version;.tar.xz">
-<!ENTITY linux-md5 "6499bdaa4ee1ef873ffd6533492140e7">
+<!ENTITY linux-md5 "50aa48ae38a736b3f313a777574af3d3">
 <!ENTITY linux-home "https://www.kernel.org/">
 <!-- measured for 5.8.3 / gcc-10.2.0 on x86_64 : minimum is
  allnoconfig extended for a hopefully-bootable build on desktop machine,