PVS-Studio warning V611 for MTASA

int CResourceChecker::ReplaceFilesInZIP(....)
{
  ....
  // Load file into a buffer
  buf = new char[ ulLength ];
  if ( fread ( buf, 1, ulLength, pFile ) != ulLength )
  {
    free( buf );
    buf = NULL;
  }
  ....
}

This suspicious code was found in MTASA project by PVS-Studio static code analyzer.
Warning message is:
V611 The memory was allocated using 'new' operator but was released using the 'free' function. Consider inspecting operation logics behind the 'buf' variable. cresourcechecker.cpp 921

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