[Full-Disclosure] DoS in PureFTPd

[Jedi/Sector One]

On Mon, Nov 10, 2003 at 04:35:06PM +0100, Adam Zabrocki wrote:
>     Vulnerability function is displayrate(). There is simple
> overflow bug (DoS):

  Killing one's own session is not a DoS.

          const size_t sizeof_resolved_path = MAXPATHLEN + 1U;	
          resolved_path[sizeof_resolved_path - 1U] = 0;	
>         if (realpath(name, resolved_path) == NULL) {
> ...
>         if (resolved_path[sizeof_resolved_path - 1U] != 0) {

  This realpath() doesn't fill more than MAXPATHLEN, including the zero, we
even have an extra byte here. The code you are talking about is not supposed
to be ever reached.

> Function realpath() is write by autor PureFTP.

  No.
  
/*
 * Copyright (c) 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Jan-Simon Pendry.
 *

  Zok.

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