diff --git a/src/Monolog/Handler/StreamHandler.php b/src/Monolog/Handler/StreamHandler.php
index a87577c8d..00bed23d4 100644
--- a/src/Monolog/Handler/StreamHandler.php
+++ b/src/Monolog/Handler/StreamHandler.php
@@ -162,7 +162,7 @@ protected function streamWrite($stream, LogRecord $record): void
         fwrite($stream, (string) $record->formatted);
     }
 
-    private function customErrorHandler(int $code, string $msg): bool
+    protected function customErrorHandler(int $code, string $msg): bool
     {
         $this->errorMessage = preg_replace('{^(fopen|mkdir)\(.*?\): }', '', $msg);