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      HEWLETT-PACKARD SECURITY BULLETIN: #00025, 2 April 95

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The information in the following Security Bulletin should be acted upon as

soon as possible. Hewlett- Packard will not be liable for any consequences

to any customer resulting from customer's failure to fully implement

instructions in this Security Bulletin as soon as possible.



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PROBLEM:  Sendmail permits unauthorized remote program execution.

PLATFORM: HP 9000 series 300/400s and 700/800s 8.x and 9.x

DAMAGE:   Remote users can cause sendmail to execute any program.

SOLUTION: Apply patch PHNE_5402 (series 700/800, HP-UX 9.x), or

                      PHNE_5401 (series 700/800, HP-UX 8.x), or

                      PHNE_5384 (series 300/400, HP-UX 9.x), or

                      PHNE_5383 (series 300/400, HP-UX 8.x), or

                      PHNE_5387 (series 700, HP-UX 9.09), or

                      PHNE_5388 (series 700, HP-UX 9.09+), or

                      PHNE_5389 (series 800, HP-UX 9.08)



AVAILABILITY: All patches are available now.

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I. Vulnerability in /usr/lib/sendmail



   A. A vulnerability in sendmail



   A vulnerability in sendmail has been discovered that permits

   remote users to cause sendmail to execute any program that is

   allowed with the permissions:



        uid=1(daemon) gid=1(other)



   Files and programs that are not world-writeable or world-executable

   and are not in the 'other' group or owned by 'daemon' are

   safe from modification.  This means that /etc/passwd cannot be

   modified, for example.



   B. Fixing the problems



   The two vulnerabilities can be eliminated from releases 8.x and 9.x of

   HP-UX by applying a patch.



   Hewlett-Packard recommends that all customers concerned with the

   security of their HP-UX systems apply the appropriate patch as

   soon as possible.



   It is further advised that system administrators closely scan their

   mail syslogs for evidence of any unusual activity, using:



        grep "|" /usr/spool/mqueue/syslog*



   [Editor's note: If your site links grep to egrep or the Gnu grep,

   the above command matches every line in the file.  An alternative is to

   use fgrep where you are looking for the "|" character. -- CERT CC]





   If there is any evidence of an intrusion, system administrators are

   strongly urged to require password changes for all accounts.





   C. How to Install the Patch (for HP-UX 8.x and 9.x)



   1.  Determine which patch is appropriate for your hardware platform

       and operating system:



         PHNE_5402 (series 700/800, HP-UX 9.x),

         PHNE_5401 (series 700/800, HP-UX 8.x),

         PHNE_5384 (series 300/400, HP-UX 9.x),

         PHNE_5383 (series 300/400, HP-UX 8.x),

         PHNE_5387 (series 700, HP-UX 9.09),

         PHNE_5388 (series 700, HP-UX 9.09+),

         PHNE_5389 (series 800, HP-UX 9.08)



   2.  Hewlett Packard's HP-UX patches are available via email

        and the World Wide Web.



        To obtain a copy of the HP SupportLine email service user's guide,

        send the following in the TEXT PORTION OF THE MESSAGE to

        support@support.mayfield.hp.com (no Subject is required):



                      send guide



        The users guide explains the process for downloading HP-UX patches

        via email and other services available.



        World Wide Web service for downloading of patches

        is available via our URL:



                http://support.mayfield.hp.com





   3.  Apply the patch to your HP-UX system.



   4.  Examine /tmp/update.log for any relevant WARNINGs or ERRORs.  This

       can be done as follows:



       a.  At the shell prompt, type "tail -60 /tmp/update.log | more"

       b.  Page through the next three screens via the space bar, looking

           for WARNING or ERROR messages.





    D. Impact of the patch and workaround



    The patch for HP-UX releases 8.x and 9.x provides a new version of

    /usr/lib/sendmail which fixes the vulnerability.  No patches will be

    available for versions of HP-UX prior to 8.0.





    E. To subscribe to automatically receive future NEW HP Security

        Bulletins from the HP SupportLine mail service via electronic

        mail, send an email message to:



                  support@support.mayfield.hp.com   (no Subject is required)



        Multiple instructions are allowed in the TEXT PORTION OF THE

        MESSAGE, here are some basic instructions you may want to use:



        To add your name to the subscription list for new security

        bulletins, send the following in the TEXT PORTION OF THE MESSAGE:



                  subscribe security_info



        To retrieve the index of all HP Security Bulletins issued to date,

        send the following in the TEXT PORTION OF THE MESSAGE:



                  send security_info_list



        To get a patch matrix of current HP-UX and BLS security

        patches referenced by either Security Bulletin or Platform/OS,

        put the following in the text portion of your message:



                  send hp-ux_patch_matrix



        World Wide Web service for browsing of bulletins

        is available via our URL:



                http://support.mayfield.hp.com



        Choose "Support news", then under Support news,

        choose "Security Bulletins"



    F. To report new security vulnerabilities, send email to



          security-alert@hp.com



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