diff --git a/src/wp-includes/post.php b/src/wp-includes/post.php
index f1ad0bde5f..dc9fb5771a 100644
--- a/src/wp-includes/post.php
+++ b/src/wp-includes/post.php
@@ -705,8 +705,6 @@ function create_initial_post_types() {
 /**
  * Retrieves attached file path based on attachment ID.
  *
- * Will return intermediate size path if the `$size` parameter is provided.
- *
  * By default the path will go through the {@see 'get_attached_file'} filter, but
  * passing `true` to the `$unfiltered` argument will return the file path unfiltered.
  *
@@ -715,28 +713,14 @@ function create_initial_post_types() {
  * a mechanism for sending the attached filename through a filter.
  *
  * @since 2.0.0
- * @since 6.2.0 The `$size` parameter was added.
  *
- * @param int          $attachment_id Attachment ID.
- * @param bool         $unfiltered    Optional. Whether to skip the {@see 'get_attached_file'} filter.
- *                                    Default false.
- * @param string|int[] $size          Optional. Image size. Accepts any registered image size name, or an array
- *                                    of width and height values in pixels (in that order). Default empty string.
+ * @param int  $attachment_id Attachment ID.
+ * @param bool $unfiltered    Optional. Whether to skip the {@see 'get_attached_file'} filter.
+ *                            Default false.
  * @return string|false The file path to where the attached file should be, false otherwise.
  */
-function get_attached_file( $attachment_id, $unfiltered = false, $size = '' ) {
-
-	// Check for intermediate sizes first, otherwise fall back to the original attachment size.
-	if ( ! empty( $size ) ) {
-		$intermediate_image = image_get_intermediate_size( $attachment_id, $size );
-		if ( ! $intermediate_image || ! isset( $intermediate_image['path'] ) ) {
-			return false;
-		}
-
-		$file = $intermediate_image['path'];
-	} else {
-		$file = get_post_meta( $attachment_id, '_wp_attached_file', true );
-	}
+function get_attached_file( $attachment_id, $unfiltered = false ) {
+	$file = get_post_meta( $attachment_id, '_wp_attached_file', true );
 
 	// If the file is relative, prepend upload dir.
 	if ( $file && 0 !== strpos( $file, '/' ) && ! preg_match( '|^.:\\\|', $file ) ) {
@@ -754,14 +738,11 @@ function get_attached_file( $attachment_id, $unfiltered = false, $size = '' ) {
 	 * Filters the attached file based on the given ID.
 	 *
 	 * @since 2.1.0
-	 * @since 6.2.0 The `$size` parameter was added.
 	 *
 	 * @param string|false $file          The file path to where the attached file should be, false otherwise.
 	 * @param int          $attachment_id Attachment ID.
-	 * @param string|int[] $size          Optional. Image size. Accepts any registered image size name, or an array
-	 *                                    of width and height values in pixels (in that order). Default empty string.
 	 */
-	return apply_filters( 'get_attached_file', $file, $attachment_id, $size );
+	return apply_filters( 'get_attached_file', $file, $attachment_id );
 }
 
 /**
diff --git a/tests/phpunit/tests/media/wpGenerateAttachmentMetadata.php b/tests/phpunit/tests/media/wpGenerateAttachmentMetadata.php
index 4afe819c51..82fe7dabd6 100644
--- a/tests/phpunit/tests/media/wpGenerateAttachmentMetadata.php
+++ b/tests/phpunit/tests/media/wpGenerateAttachmentMetadata.php
@@ -18,7 +18,6 @@ class Tests_Media_wpGenerateAttachmentMetadata extends WP_UnitTestCase {
 	 * Tests that filesize meta is generated for JPEGs.
 	 *
 	 * @ticket 49412
-	 * @ticket 51780
 	 *
 	 * @covers ::wp_create_image_subsizes
 	 */
@@ -29,11 +28,10 @@ class Tests_Media_wpGenerateAttachmentMetadata extends WP_UnitTestCase {
 
 		$this->assertSame( wp_filesize( get_attached_file( $attachment ) ), $metadata['filesize'] );
 
-		foreach ( $metadata['sizes'] as $size => $intermediate_size ) {
+		foreach ( $metadata['sizes'] as $intermediate_size ) {
 			$this->assertArrayHasKey( 'filesize', $intermediate_size );
 			$this->assertNotEmpty( $intermediate_size['filesize'] );
 			$this->assertIsNumeric( $intermediate_size['filesize'] );
-			$this->assertStringContainsString( $intermediate_size['file'], get_attached_file( $attachment, false, $size ) );
 		}
 	}