diff --git a/NEWS b/NEWS
index 4938b79b0713..048976ba346a 100644
--- a/NEWS
+++ b/NEWS
@@ -169,6 +169,7 @@ PHP                                                                        NEWS
     rmdir(), touch(), chmod() or stat(). (Ilia Alshanetsky)
 
 - Standard:
+  . Made extension names in ini_get_all() case-insensitive. (Weilin Du)
   . Fixed bug GH-25387 (Uploaded files leak in request_parse_body()).
     (Kévin Dunglas)
   . Fixed quoted_printable_decode() truncating input at NUL bytes. (Weilin Du)
diff --git a/UPGRADING b/UPGRADING
index d9242ecb3c17..4f9c01765908 100644
--- a/UPGRADING
+++ b/UPGRADING
@@ -60,6 +60,11 @@ PHP 8.7 UPGRADE NOTES
     application terminate one attribute and append further ones.
 
 - Standard:
+  . ini_get_all() now matches extension names case-insensitively using ASCII
+    rules, independently of the current locale. Names that differ only in
+    capitalization from a loaded extension now succeed instead of emitting a
+    warning and returning false.
+    RFC: https://wiki.php.net/rfc/case_insensitive_ini_get_all
   . bindec(), octdec(), hexdec() and base_convert() now throw an Exception
     when the passed string contains characters that are invalid for the
     specified number base.
diff --git a/ext/standard/basic_functions.c b/ext/standard/basic_functions.c
index db302ab724ab..9ae99b6f1eed 100644
--- a/ext/standard/basic_functions.c
+++ b/ext/standard/basic_functions.c
@@ -1950,7 +1950,7 @@ PHP_FUNCTION(ini_get_all)
 	zend_ini_sort_entries();
 
 	if (extname) {
-		if ((module = zend_hash_find_ptr(&module_registry, extname)) == NULL) {
+		if ((module = zend_hash_find_ptr_lc(&module_registry, extname)) == NULL) {
 			php_error_docref(NULL, E_WARNING, "Extension \"%pS\" cannot be found", extname);
 			RETURN_FALSE;
 		}
diff --git a/ext/standard/tests/general_functions/ini_get_all_case_insensitive.phpt b/ext/standard/tests/general_functions/ini_get_all_case_insensitive.phpt
new file mode 100644
index 000000000000..fe1cd3350e17
--- /dev/null
+++ b/ext/standard/tests/general_functions/ini_get_all_case_insensitive.phpt
@@ -0,0 +1,36 @@
+--TEST--
+ini_get_all() accepts case-insensitive extension names
+--FILE--
+<?php
+foreach (['PCRE', 'Pcre', 'pCrE'] as $extension) {
+    var_dump(ini_get_all($extension) === ini_get_all('pcre'));
+    var_dump(ini_get_all($extension, true) === ini_get_all('pcre', true));
+    var_dump(ini_get_all($extension, false) === ini_get_all('pcre', false));
+}
+
+var_dump(ini_get_all('REFLECTION'));
+var_dump(ini_get_all('Reflection', false));
+
+var_dump(ini_get_all('NoSuchExtension'));
+var_dump(ini_get_all('NoSuchExtension', false));
+?>
+--EXPECTF--
+bool(true)
+bool(true)
+bool(true)
+bool(true)
+bool(true)
+bool(true)
+bool(true)
+bool(true)
+bool(true)
+array(0) {
+}
+array(0) {
+}
+
+Warning: ini_get_all(): Extension "NoSuchExtension" cannot be found in %s on line %d
+bool(false)
+
+Warning: ini_get_all(): Extension "NoSuchExtension" cannot be found in %s on line %d
+bool(false)