diff --git a/download b/download
index 166fffdb69d9ed3890296c55ff4d4084f726d048..8a9b24484e9a20e10c72de98001def5d4e3b23eb 100644
--- a/download
+++ b/download
@@ -1,6 +1,6 @@
 9b999bdcf031e29a4d8ce2b6f17e778e  cbindgen-vendor.tar.xz
-d5642fea03bb23621bdf2dc15180d2e9  firefox-115.4.0esr.processed-source.tar.xz
-128855d07f1b2afa9e1f1da302f07522  firefox-langpacks-115.4.0esr-20231017.tar.xz
+26a6d8a9440ba4d7d5e5c85b7453022a  firefox-115.5.0esr.processed-source.tar.xz
+5dd9d96d19ff3368ab18f3a1ef42bc41  firefox-langpacks-115.5.0esr-20231114.tar.xz
 b3c1d2ea615cb0195f4f62b005773262  mochitest-python.tar.gz
 7b35b9a003996b1f1dbc3cd936a609f2  nspr-4.35.0-1.el8_1.src.rpm
 3fdd30cefe44a98c424cb3aeca73f2b3  nss-3.90.0-3.el8_1.src.rpm
diff --git a/firefox.spec b/firefox.spec
index 27ad59d361a9d10d2e03e44a823e5ba3af9b6653..ff876f34959c12ea6c5d986340ffe3b599dc7d7f 100644
--- a/firefox.spec
+++ b/firefox.spec
@@ -25,7 +25,7 @@ function dist_to_rhel_minor(str, start)
   end
   match = string.match(str, ".an8")
   if match then
-     return 8
+     return 10
   end
   match = string.match(str, ".module%+el9.%d+")
   if match then
@@ -37,7 +37,7 @@ function dist_to_rhel_minor(str, start)
   end
   match = string.match(str, ".el9")
   if match then
-     return 3
+     return 4
   end
   return -1
 end}
@@ -133,7 +133,7 @@ end}
 
 Summary:              Mozilla Firefox Web browser
 Name:                 firefox
-Version:              115.4.0
+Version:              115.5.0
 Release:              1%{anolis_release}%{?dist}
 URL:                  https://www.mozilla.org/firefox/
 License:              MPLv1.1 or GPLv2+ or LGPLv2+
@@ -144,10 +144,15 @@ ExcludeArch:  loongarch64
 ExcludeArch:          %{ix86}
 %endif
 %if 0%{?rhel} == 8
+  # Started to ship on aarch64 in RHEL 8.2, on s390x in RHEL 8.3
   %if %{rhel_minor_version} == 1
-ExcludeArch:          %{ix86} aarch64 s390x
+ExcludeArch:          %{ix86} s390x aarch64
   %else
+    %if %{rhel_minor_version} == 2
+ExcludeArch:          %{ix86} s390x
+    %else
 ExcludeArch:          %{ix86}
+    %endif
   %endif
 %endif
 %if 0%{?rhel} == 7
@@ -161,7 +166,7 @@ ExcludeArch:          aarch64 s390 ppc
 # Link to original tarball: https://archive.mozilla.org/pub/firefox/releases/%%{version}%%{?pre_version}/source/firefox-%%{version}%%{?pre_version}.source.tar.xz
 Source0:              firefox-%{version}%{?pre_version}%{?buildnum}.processed-source.tar.xz
 %if %{with langpacks}
-Source1:              firefox-langpacks-%{version}%{?pre_version}-20231017.tar.xz
+Source1:              firefox-langpacks-%{version}%{?pre_version}-20231114.tar.xz
 %endif
 Source2:              cbindgen-vendor.tar.xz
 Source3:              process-official-tarball
@@ -1119,6 +1124,13 @@ echo "ac_add_options --with-mozilla-api-keyfile=`pwd`/mozilla-api-key" >> .mozco
 echo "ac_add_options --with-google-location-service-api-keyfile=`pwd`/google-loc-api-key" >> .mozconfig
 echo "ac_add_options --with-google-safebrowsing-api-keyfile=`pwd`/google-api-key" >> .mozconfig
 
+# May result in empty --with-libclang-path= in earlier versions.
+# So far this is needed only for c8s.
+%if 0%{?rhel} == 8 && %{rhel_minor_version} >= 10
+# Clang 17 upstream's detection fails, tell it where to look.
+echo "ac_add_options --with-libclang-path=`llvm-config --libdir`" >> .mozconfig
+%endif
+
 echo 'export NODEJS="%{_buildrootdir}/bin/node-stdout-nonblocking-wrapper"' >> .mozconfig
 
 # Remove executable bit to make brp-mangle-shebangs happy.
@@ -1730,10 +1742,13 @@ gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :
 #---------------------------------------------------------------------
 
 %changelog
-* Wed Nov 1 2023 Liwei Ge <geliwei@openanolis.org> - 115.4.0-1.0.1
+* Fri Dec 01 2023 Liwei Ge <geliwei@openanolis.org> - 115.5.0-1.0.1
 - Add firefox-anolis-default-prefs.js
 - Remove bookmarks and loongarch64
 
+* Tue Nov 14 2023 Eike Rathke <erack@redhat.com> - 115.5.0-1
+- Update to 115.5.0 build1
+
 * Tue Oct 17 2023 Eike Rathke <erack@redhat.com> - 115.4.0-1
 - Update to 115.4.0 build1
 - Add fix for CVE-2023-44488