diff --git a/NEWS b/NEWS
index 12d15e699f1f..a1848fa9bb1d 100644
--- a/NEWS
+++ b/NEWS
@@ -104,6 +104,8 @@ PHP                                                                        NEWS
 - Session:
   . Fixed session data loss in the files save handler when writing the session
     file fails after it was already truncated. (Ilia Alshanetsky)
+  . Fixed bug GH-24493 (Upload progress handler destroys the session when an
+    object has an incomplete class property name). (Lazizbek Ergashev)
 
 - Standard:
   . Fixed bug GH-24399 (usleep() and time_nanosleep() ignore queued APCs on
diff --git a/ext/session/session.c b/ext/session/session.c
index 7a57652f55d1..102f36c9a524 100644
--- a/ext/session/session.c
+++ b/ext/session/session.c
@@ -266,6 +266,11 @@ static zend_string *php_session_encode(void) /* {{{ */
 
 static ZEND_COLD void php_session_cancel_decode(void)
 {
+	if (PS(in_rfc1867_update)) {
+		/* Leave the record alone, the request decodes it without these limits */
+		php_session_abort();
+		return;
+	}
 	php_session_destroy();
 	php_session_track_init();
 	php_error_docref(NULL, E_WARNING, "Failed to decode session object. Session has been destroyed");
diff --git a/ext/session/tests/rfc1867_incomplete_class_reserved_props.phpt b/ext/session/tests/rfc1867_incomplete_class_reserved_props.phpt
index 954e46b7116b..ee436d57a8f4 100644
--- a/ext/session/tests/rfc1867_incomplete_class_reserved_props.phpt
+++ b/ext/session/tests/rfc1867_incomplete_class_reserved_props.phpt
@@ -1,5 +1,5 @@
 --TEST--
-session rfc1867: the upload progress update rejects session data whose objects carry the incomplete class bookkeeping property names
+session rfc1867: the upload progress update leaves session data alone when its objects carry the incomplete class bookkeeping property names
 --EXTENSIONS--
 session
 --SKIPIF--
@@ -23,7 +23,9 @@ file_put_contents($worker, '<?php');
  * __PHP_Incomplete_Class, which stores the class name of each object and the
  * payload of C:/E: entries under these three property names. Data that already
  * carries one of them cannot be told apart from that bookkeeping, so the decode
- * has to fail rather than let the two meanings be confused. */
+ * has to fail rather than let the two meanings be confused. The handler then
+ * skips the update and leaves the record to the request, which decodes it
+ * without these limits. */
 $cases = [
     'control'          => 'x|O:8:"stdClass":1:{s:1:"a";i:1;}',
     'Class_Name'       => 'x|O:8:"stdClass":1:{s:27:"__PHP_Incomplete_Class_Name";s:3:"foo";}',
@@ -109,9 +111,6 @@ foreach ($cases as $label => $record) {
     fclose($pipes[2]);
     proc_close($proc);
 
-    /* A refused decode must leave exactly one warning: the handler stops there
-     * instead of writing the progress into the empty session it was left with,
-     * which would add a second warning about the save path. */
     $kept = file_exists($file) && str_starts_with(file_get_contents($file), $record);
     printf("%-16s warnings: %d, decode refused: %-5s record kept: %s\n", $label,
         substr_count($out, 'Warning:'),
@@ -131,9 +130,9 @@ foreach (glob("$dir/sess_*") as $f) {
 ?>
 --EXPECT--
 control          warnings: 0, decode refused: false record kept: true
-Class_Name       warnings: 1, decode refused: true  record kept: false
-Class_Serialized warnings: 1, decode refused: true  record kept: false
-Enum_Case        warnings: 1, decode refused: true  record kept: false
-nested           warnings: 1, decode refused: true  record kept: false
+Class_Name       warnings: 0, decode refused: false record kept: true
+Class_Serialized warnings: 0, decode refused: false record kept: true
+Enum_Case        warnings: 0, decode refused: false record kept: true
+nested           warnings: 0, decode refused: false record kept: true
 mangled          warnings: 0, decode refused: false record kept: true
-corrupt          warnings: 1, decode refused: true  record kept: false
+corrupt          warnings: 0, decode refused: false record kept: true