diff --git a/src/com/jpexs/helpers/MemoryInputStream.java b/src/com/jpexs/helpers/MemoryInputStream.java
index bcef7826b..9c3da11f7 100644
--- a/src/com/jpexs/helpers/MemoryInputStream.java
+++ b/src/com/jpexs/helpers/MemoryInputStream.java
@@ -60,6 +60,9 @@ public class MemoryInputStream extends SeekableInputStream {
 
     @Override
     public void seek(long pos) throws IOException {
+        if (pos < 0) {
+            throw new IOException("Seek to negative position");
+        }
         this.pos = pos;
     }