Merge commit from fork

CVE-2026-41252: lib_palette_update Heap Buffer Overflow

vnc/vnc.c

@@ -1649,6 +1649,13 @@ lib_palette_update(struct vnc *v)
         in_uint8s(s, 1);
         in_uint16_be(s, first_color);
         in_uint16_be(s, num_colors);
+        if ((first_color + num_colors) > VNC_PALETTE_SIZE)
+        {
+            LOG(LOG_LEVEL_ERROR, "lib_palette_update: palette overflow");
+            free_stream(s);
+            return 1;
+        }
+
         init_stream(s, 8192);
         error = trans_force_read_s(v->trans, s, num_colors * 6);
     }

vnc/vnc.h

@@ -76,6 +76,8 @@ struct xrdp_client_info;
 /* Defined in vnc_clip.c */
 struct vnc_clipboard_data;
 
+#define VNC_PALETTE_SIZE 256
+
 /* Defined in xrdp_client_info.h */
 struct monitor_info;
 
@@ -167,7 +169,7 @@ struct vnc
     int server_bpp;
     char mod_name[256];
     int mod_mouse_state;
-    int palette[256];
+    int palette[VNC_PALETTE_SIZE];
     int vnc_desktop;
     char username[256];
     char password[256];