diff --git a/expat-2.2.10-Detect-and-prevent-integer-overflow-in-XML_GetBuffer.patch b/expat-2.2.10-Detect-and-prevent-integer-overflow-in-XML_GetBuffer.patch
new file mode 100644
index 0000000..58d9941
--- /dev/null
+++ b/expat-2.2.10-Detect-and-prevent-integer-overflow-in-XML_GetBuffer.patch
@@ -0,0 +1,62 @@
+diff --git a/lib/xmlparse.c b/lib/xmlparse.c
+index d54af683..5ce31402 100644
+--- a/lib/xmlparse.c
++++ b/lib/xmlparse.c
+@@ -2067,6 +2067,11 @@ XML_GetBuffer(XML_Parser parser, int len) {
+     keep = (int)EXPAT_SAFE_PTR_DIFF(parser->m_bufferPtr, parser->m_buffer);
+     if (keep > XML_CONTEXT_BYTES)
+       keep = XML_CONTEXT_BYTES;
++    /* Detect and prevent integer overflow */
++    if (keep > INT_MAX - neededSize) {
++      parser->m_errorCode = XML_ERROR_NO_MEMORY;
++      return NULL;
++    }
+     neededSize += keep;
+ #endif /* defined XML_CONTEXT_BYTES */
+     if (neededSize
+diff --git a/tests/runtests.c b/tests/runtests.c
+index e89e8220..579dad1a 100644
+--- a/tests/runtests.c
++++ b/tests/runtests.c
+@@ -3847,6 +3847,30 @@ START_TEST(test_get_buffer_2) {
+ }
+ END_TEST
+ 
++/* Test for signed integer overflow CVE-2022-23852 */
++#if defined(XML_CONTEXT_BYTES)
++START_TEST(test_get_buffer_3_overflow) {
++  XML_Parser parser = XML_ParserCreate(NULL);
++  assert(parser != NULL);
++
++  const char *const text = "\n";
++  const int expectedKeepValue = (int)strlen(text);
++
++  // After this call, variable "keep" in XML_GetBuffer will
++  // have value expectedKeepValue
++  if (XML_Parse(parser, text, (int)strlen(text), XML_FALSE /* isFinal */)
++      == XML_STATUS_ERROR)
++    xml_failure(parser);
++
++  assert(expectedKeepValue > 0);
++  if (XML_GetBuffer(parser, INT_MAX - expectedKeepValue + 1) != NULL)
++    fail("enlarging buffer not failed");
++
++  XML_ParserFree(parser);
++}
++END_TEST
++#endif // defined(XML_CONTEXT_BYTES)
++
+ /* Test position information macros */
+ START_TEST(test_byte_info_at_end) {
+   const char *text = "<doc></doc>";
+@@ -11731,6 +11755,9 @@ make_suite(void) {
+   tcase_add_test(tc_basic, test_empty_parse);
+   tcase_add_test(tc_basic, test_get_buffer_1);
+   tcase_add_test(tc_basic, test_get_buffer_2);
++#if defined(XML_CONTEXT_BYTES)
++  tcase_add_test(tc_basic, test_get_buffer_3_overflow);
++#endif
+   tcase_add_test(tc_basic, test_byte_info_at_end);
+   tcase_add_test(tc_basic, test_byte_info_at_error);
+   tcase_add_test(tc_basic, test_byte_info_at_cdata);
+
diff --git a/expat.spec b/expat.spec
index 023caf6..324375f 100644
--- a/expat.spec
+++ b/expat.spec
@@ -3,7 +3,7 @@
 Summary: An XML parser library
 Name: expat
 Version: %(echo %{unversion} | sed 's/_/./g')
-Release: 8%{?dist}
+Release: 9%{?dist}
 Source: https://github.com/libexpat/libexpat/archive/R_%{unversion}.tar.gz#/expat-%{version}.tar.gz
 URL: https://libexpat.github.io/
 License: MIT
@@ -13,6 +13,7 @@ Patch0:	expat-2.2.10-prevent-integer-overflow-in-doProlog.patch
 Patch1:	expat-2.2.10-Prevent-more-integer-overflows.patch
 Patch2:	expat-2.2.10-Prevent-integer-overflow-on-m_groupSize-in-function.patch
 Patch3:	expat-2.2.10-Detect-and-prevent-troublesome-left-shifts.patch
+Patch4:	expat-2.2.10-Detect-and-prevent-integer-overflow-in-XML_GetBuffer.patch
 
 %description
 This is expat, the C library for parsing XML, written by James Clark. Expat
@@ -44,6 +45,7 @@ Install it if you need to link statically with expat.
 %patch1 -p1 -b .CVE-2022-22822-CVE-2022-22827
 %patch2 -p1 -b .CVE-2021-46143
 %patch3 -p1 -b .CVE-2021-45960
+%patch4 -p1 -b .CVE-2022-23852
 
 sed -i 's/install-data-hook/do-nothing-please/' lib/Makefile.am
 ./buildconf.sh
@@ -81,6 +83,10 @@ make check
 %{_libdir}/lib*.a
 
 %changelog
+* Thu Feb 10 2022 Tomas Korbar <tkorbar@redhat.com> -  2.2.10-9
+- CVE-2022-23852 expat: integer overflow in function XML_GetBuffer
+- Resolves: CVE-2022-23852
+
 * Thu Feb 10 2022 Tomas Korbar <tkorbar@redhat.com> -  2.2.10-8
 - CVE-2021-45960 expat: Large number of prefixed XML attributes on a single tag can crash libexpat
 - Resolves: CVE-2021-45960