diff -up libpng-1.6.40/pngrutil.c.fix_sast libpng-1.6.40/pngrutil.c
--- libpng-1.6.40/pngrutil.c.fix_sast	2024-08-06 15:35:51.789156138 +0200
+++ libpng-1.6.40/pngrutil.c	2024-08-06 15:35:51.816156415 +0200
@@ -1815,7 +1815,7 @@ png_handle_sPLT(png_structrp png_ptr, pn
 void /* PRIVATE */
 png_handle_tRNS(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
 {
-   png_byte readbuf[PNG_MAX_PALETTE_LENGTH];
+   png_byte readbuf[PNG_MAX_PALETTE_LENGTH] = {0};
 
    png_debug(1, "in png_handle_tRNS");