lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [day] [month] [year] [list]
Message-ID: <20030428092256.CC6DD33919@mail1.tamperd.net>
Date: Mon, 28 Apr 2003 11:22:55 +0200
From: Daniel Ahlberg <aliz@...too.org>
To: bugtraq@...urityfocus.com
Subject: GLSA:  pptpd (200304-08)


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

- - - ---------------------------------------------------------------------
GENTOO LINUX SECURITY ANNOUNCEMENT 200304-08
- - - ---------------------------------------------------------------------

          PACKAGE : pptpd
          SUMMARY : buffer overflow
             DATE : 2003-04-28 09:22 UTC
          EXPLOIT : remote
VERSIONS AFFECTED : <pptpd-1.1.3.20030429
    FIXED VERSION : >=pptpd-1.1.3.20030429
              CVE : CAN-2003-0213

- - - ---------------------------------------------------------------------

- - From advisory:

"PPTP packet header contain 16bit length which specifies the full size of
the packet:

        bytes_this = read(clientFd, packet + bytes_ttl, 2 - bytes_ttl);
        // ...
        bytes_ttl += bytes_this;
        // ...
        length = htons(*(u_int16_t *) packet);
        if (length > PPTP_MAX_CTRL_PCKT_SIZE) {
          // abort
        }

Looks good so far, except:

        bytes_this = read(clientFd, packet + bytes_ttl, length - bytes_ttl);

If given length was 0 or 1, the "length - bytes_ttl" result is -1 or -2,
which means that it reads unlimited amount of data from client into
"packet", which is a buffer located in stack.

The exploitability only depends on if libc allows the size parameter to be
larger than SSIZE_MAX bytes. GLIBC does, Solaris and *BSD don't."

Read the full advisory at:
http://marc.theaimsgroup.com/?l=bugtraq&m=104994375011406&w=2

SOLUTION

It is recommended that all Gentoo Linux users who are running
net-dialup/pptpd upgrade to pptpd-1.1.3.20030409 as follows:

emerge sync
emerge pptpd
emerge clean

- - - ---------------------------------------------------------------------
aliz@...too.org - GnuPG key is available at http://cvs.gentoo.org/~aliz
- - - ---------------------------------------------------------------------
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.1 (GNU/Linux)

iD8DBQE+rPLrfT7nyhUpoZMRAjKOAJ9Ztnuvpr6luyiBl+CD2PzlOHBKKgCfWlT+
A6YGzE9MLzvOleHHY9u1ivA=
=hi8d
-----END PGP SIGNATURE-----


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ