Home page logo
/

oss-sec logo oss-sec mailing list archives

Re: CVE Request -- mcrypt: stack-based buffer overflow by encryption / decryption of overly long file names
From: "Steven M. Christey" <coley () rcf-smtp mitre org>
Date: Mon, 19 Nov 2012 22:12:04 -0500 (EST)


For my own clarification - where does this long file name come from? If it's only provided on the command line, then I don't see how this would be a vulnerability, since the person executing mcrypt would only be attacking themselves. (CVE-2012-4409 is still OK since one wouldn't expect code execution when decrypting the contents of a file.)

Thanks,
Steve


On Thu, 18 Oct 2012, Kurt Seifried wrote:

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 10/18/2012 07:50 AM, Jan Lieskovsky wrote:
Hello Kurt, Steve, vendors,

  Attila Bogar reported a stack-based buffer overflow
in the way MCrypt, a crypt() package and crypt(1) command
replacement, used to encrypt / decrypt files with overly
long names (longer than 128 bytes). A remote attacker
could provide a specially-crafted file that, when processed
by the mcrypt too, would lead to mcrypt executable crash [*].

A different vulnerability than CVE-2012-4409:
[1] https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2012-4409

Note: Using Red Hat bugzilla record for CVE-2012-4409 since
particular Mitre record is not described yet.

References:
[2] https://bugzilla.redhat.com/show_bug.cgi?id=867790

Patch proposed by Attila:
[3] https://bugzilla.redhat.com/show_bug.cgi?id=867790#c0

Reproducer:
To reproduce let mcrypt encrypt / decrypt file with name
longer ~128 bytes.

Could you allocate a CVE id for this?

Thank you && Regards, Jan.
--
Jan iankko Lieskovsky / Red Hat Security Response Team

[*] FORTIFY_SOURCE protection mechanism would mitigate this
deficiency to result into crash only. But on systems, without
FORTIFY_SOURCE protection being applied, the impact might be
higher.

P.S.: I am not sure about relation of this issue to the issue
      Raphael Geissert reported previously:
      [4] http://www.openwall.com/lists/oss-security/2012/10/02/1

      so CC-in him too, he to clarify if [2] == [4], or if
      they are yet different issues. Raphael, please clarify.
      Thanks, Jan.


Please use CVE-2012-4527 for this issue.

- --
Kurt Seifried Red Hat Security Response Team (SRT)
PGP: 0x5E267993 A90B F995 7350 148F 66BF 7554 160D 4553 5E26 7993

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://www.enigmail.net/
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=TH3z
-----END PGP SIGNATURE-----



  By Date           By Thread  

Current thread:
[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]