diff --git a/SOURCES/boost-1.75.0-json-endian.patch b/SOURCES/boost-1.75.0-json-endian.patch
new file mode 100644
index 0000000..e0c9cca
--- /dev/null
+++ b/SOURCES/boost-1.75.0-json-endian.patch
@@ -0,0 +1,41 @@
+From 8ad666f05367c185598816a3153e05a976ffe920 Mon Sep 17 00:00:00 2001
+From: Dmitry Arkhipov <grisumbras@gmail.com>
+Date: Thu, 9 Jun 2022 18:59:42 +0300
+Subject: [PATCH] deduce endianness of the platform
+
+---
+ boost/json/detail/config.hpp | 18 ++++++++++++++++++
+ 1 file changed, 18 insertions(+)
+
+diff --git a/include/boost/json/detail/config.hpp b/include/boost/json/detail/config.hpp
+index 398f789..62a65d1 100644
+--- a/boost/json/detail/config.hpp
++++ b/boost/json/detail/config.hpp
+@@ -250,6 +250,24 @@
+ # endif
+ #endif
+ 
++
++#if ! defined(BOOST_JSON_BIG_ENDIAN) && ! defined(BOOST_JSON_LITTLE_ENDIAN)
++// Copied from Boost.Endian
++# if defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
++#  define BOOST_JSON_LITTLE_ENDIAN
++# elif defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
++#  define BOOST_JSON_BIG_ENDIAN
++# elif defined(__LITTLE_ENDIAN__)
++#  define BOOST_JSON_LITTLE_ENDIAN
++# elif defined(__BIG_ENDIAN__)
++#  define BOOST_JSON_BIG_ENDIAN
++# elif defined(_MSC_VER) || defined(__i386__) || defined(__x86_64__)
++#  define BOOST_JSON_LITTLE_ENDIAN
++# else
++#  error The Boost.JSON library could not determine the endianness of this platform. Define either BOOST_JSON_BIG_ENDIAN or BOOST_JSON_LITTLE_ENDIAN.
++# endif
++#endif
++
+ BOOST_JSON_NS_BEGIN
+ namespace detail {
+ 
+-- 
+2.51.0.463.g79cf913ea9
+
diff --git a/SPECS/boost.spec b/SPECS/boost.spec
index 3f4d2d0..90dc829 100644
--- a/SPECS/boost.spec
+++ b/SPECS/boost.spec
@@ -42,7 +42,7 @@ Name: boost
 %global real_name boost
 Summary: The free peer-reviewed portable C++ source libraries
 Version: 1.75.0
-Release: 12%{?dist}
+Release: 13%{?dist}
 License: Boost and MIT and Python
 
 # Replace each . with _ in %%{version}
@@ -165,6 +165,10 @@ Patch98: boost-1.75-asio-fix.patch
 # https://github.com/boostorg/filesystem/issues/254
 Patch99: boost-1.75.0-copy_file-exdev.patch
 
+# https://issues.redhat.com/browse/RHEL-120655
+# https://github.com/boostorg/json/issues/717
+Patch100: boost-1.75.0-json-endian.patch
+
 %bcond_with tests
 %bcond_with docs_generated
 
@@ -691,6 +695,7 @@ find ./boost -name '*.hpp' -perm /111 | xargs chmod a-x
 %patch -P95 -p1
 %patch -P98 -p1
 %patch -P99 -p1
+%patch -P100 -p1
 
 %build
 %set_build_flags
@@ -1296,6 +1301,9 @@ fi
 %{_mandir}/man1/b2.1*
 
 %changelog
+* Thu Nov 4 2025 Patrick Palka <ppalka@redhat.com> - 1.75.0-13
+- Add Boost.JSON patch for detecting endianness (RHEL-120655)
+
 * Tue Jul 8 2025 Patrick Palka <ppalka@redhat.com> - 1.75.0-12
 - Fix the CMake config file for openmpi and mpich (RHEL-97588)