oss-security - Re: CVE id request: shttpd/mongoose/yassl embedded webserver

Follow @Openwall on Twitter for new release announcements and other news

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date: Wed, 3 Aug 2011 17:00:17 -0400 (EDT)
From: Josh Bressers <bressers@...hat.com>
To: oss-security@...ts.openwall.com
Cc: coley <coley@...re.org>
Subject: Re: CVE id request: shttpd/mongoose/yassl embedded
 webserver

Please use CVE-2011-2900.

Thanks.

-- 
    JB


----- Original Message -----
> Hi,
> I found a buffer overflow in the PUT processing of
> shttpd/mongoose/yassl
> embedded webserver (all based on the same source code).
> 
> Can someone assign a CVE id to this?
> Upstream fix:
> https://code.google.com/p/mongoose/source/detail?r=556f4de91eae4bac40dc5d4ddbd9ec7c424711d0#
> 
> The bug:
> _shttpd_put_dir()/put_dir() function:
> 26 for (s = p = path + 2; (p = strchr(s, '/')) != NULL; s = ++p) {
> 27 len = p - path;
> 28 assert(len < sizeof(buf));
> 29 (void) memcpy(buf, path, len);
> 30 buf[len] = '\0';
> 31
> 32 /* Try to create intermediate directory */
> 33 if (_shttpd_stat(buf, &st) == -1 &&
> 34 _shttpd_mkdir(buf, 0755) != 0)
> 35 return (-1);
> 36
> 37 /* Is path itself a directory ? */
> 38 if (p[1] == '\0')
> 39 return (0);
> 40 }
> 
> The only guard here to avoid a buffer overflow with a long path is
> the assert call in line 28. Unfortunately this is disabled if
> you compile with -DNDEBUG and from what I see quite a lot of people
> are doing that in order to reduce the binary size (those are embedded
> webservers intended to be used in embedded environments).
> 
> It seems quite some projects actually do that, including a
> deployed product embedded product I'm currently
> looking at (and that was rooted because of this bug).
> From what I see -DNDEBUG in the mongoose makefile this is also the
> default for the mingw
> binary.
> 
> If this is not the case, this is still a DoS bug.
> 
> Kind regards
> Nico
> --
> Nico Golde - http://www.ngolde.de - nion@...ber.ccc.de - GPG:
> 0xA0A0AAAA
> For security reasons, all text in this mail is double-rot13 encrypted.

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.