Vulnerability Note VU#387387

Common Desktop Environment (CDE) ToolTalk RPC database server (rpc.ttdbserverd) vulnerable to buffer overflow via _TT_CREATE_FILE()

The ToolTalk RPC database server is vulnerable to a heap buffer overflow via an argument to the procedure _TT_CREATE_FILE(). As noted by the reporter, the non-executable stack feature of some operating systems may not prevent exploitation of this vulnerability if the payload can be located on the heap. An attacker with access to the ToolTalk RPC database service could exploit this vulnerability with a specially crafted RPC message.

II. Impact

Apply a Patch

Apply the appropriate patch from your vendor as specified in the Systems Affected section below.

Disable rpc.ttdbserverd

Until patches are available and can be applied, you may wish to consider disabling the ToolTalk RPC database service. As a general best practice, the CERT/CC recommends disabling any services that are not explicitly required. The ToolTalk RPC database service may be enabled in /etc/rpc or in /etc/inetd.conf. For example, on a Solaris 8 system, comment out the following entry in /etc/inetd.conf to disable the ToolTalk RPC database service (rpc.ttdbserverd):

#
# Sun ToolTalk Database Server
#
100083/1        tli     rpc/tcp wait root /usr/dt/bin/rpc.ttdbserverd rpc.ttdbserverd

The rpcinfo(1M) and ps(1) commands may be useful in determining if you system is running the ToolTalk RPC database server. On a Solaris 8 system, the following examples indicate that the ToolTalk RPC database server is running:

# rpcinfo -p | grep 100083
    100083    1   tcp   32773

# ps -ef | grep rpc.ttdbserverd
    root   355   164  0  19:31:27 ?        0:00 rpc.ttdbserverd

Block or Restrict Access

Until patches are available and can be applied, block or restrict access to the RPC portmapper service and the ToolTalk RPC database service from untrusted networks such as the Internet. Using a firewall or other packet-filtering technology, block the ports used by the RPC portmapper and ToolTalk RPC services. The RPC portmapper service typically runs on ports 111/tcp and 111/udp. The ToolTalk RPC service may be configured to use port 692/tcp or another port as indicated in output from the rpcinfo command. Keep in mind that blocking ports at a network perimeter does not protect the vulnerable service from the internal network. It is important to understand your network configuration and service requirements before deciding what changes are appropriate.

Systems Affected

http://www.entercept.com/news/uspr/08-12-02.asp
http://www.securityfocus.com/bid/5444

Credit

The CERT/CC thanks Sinan Eren of the Entercept Ricochet Team for reporting this vulnerability.

This document was written by Art Manion.

Other Information

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