a1d952
@@ -922,7 +922,7 @@
private boolean bufferContainsSignature(final ByteArrayOutputStream bos, final i
 
         boolean done = false;
         int readTooMuch = 0;
-        for (int i = 0; !done && i < lastRead - 4; i++) {
+        for (int i = 0; !done && i < offset + lastRead - 4; i++) {
             if (buf.array()[i] == LFH[0] && buf.array()[i + 1] == LFH[1]) {
                 if ((buf.array()[i + 2] == LFH[2] && buf.array()[i + 3] == LFH[3])
                     || (buf.array()[i] == CFH[2] && buf.array()[i + 3] == CFH[3])) {
