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1.1       deraadt     1: <!DOCTYPE HTML PUBLIC  "-//IETF//DTD HTML Strict//EN">
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                      3: <head>
1.20      deraadt     4: <title>OpenBSD Security</title>
1.1       deraadt     5: <link rev=made href=mailto:www@openbsd.org>
                      6: <meta name="resource-type" content="document">
                      7: <meta name="description" content="OpenBSD advisories">
                      8: <meta name="keywords" content="openbsd,main">
                      9: <meta name="distribution" content="global">
1.45      deraadt    10: <meta name="copyright" content="This document copyright 1997,1998 by OpenBSD.">
1.1       deraadt    11: </head>
                     12:
                     13: <BODY BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#23238E">
                     14:
1.77      deraadt    15: <img alt="[OpenBSD]" height=30 width=141 SRC="images/smalltitle.gif">
1.1       deraadt    16:
1.56      deraadt    17: <hr>
                     18: <a href=#21>For 2.1 security advisories, please refer here</a>.<br>
                     19: <a href=#22>For 2.2 security advisories, please refer here</a>.<br>
                     20: <a href=#23>For 2.3 security advisories, please refer here</a>.<br>
1.75      deraadt    21: <a href=#24>For 2.4 security advisories, please refer here</a>.<br>
1.56      deraadt    22: <hr>
                     23:
1.2       deraadt    24: <p>
1.12      deraadt    25: <h3><font color=#e00000><strong>OpenBSD Security Views</strong></font></h3>
1.22      deraadt    26:
1.14      deraadt    27: OpenBSD believes in strong security.  Our aspiration is to be NUMBER
1.22      deraadt    28: ONE in the industry for security (if we are not already there).  Our
                     29: open software development model permits us to take a more
                     30: uncompromising view towards increased security than Sun, SGI, IBM, HP,
                     31: or other vendors are able to.  We can make changes the vendors would
1.27      deraadt    32: not make.  Also, since OpenBSD is exported with <a href=crypto.html>
1.45      deraadt    33: cryptography</a>, we are able to take cryptographic approaches towards
                     34: fixing security problems.<p>
1.18      deraadt    35:
1.45      deraadt    36: Like many readers of the
1.13      deraadt    37: <a href=http://www.geek-girl.com/bugtraq/index.html>
1.18      deraadt    38: BUGTRAQ mailing list</a>,
1.45      deraadt    39: we believe in full disclosure of security problems.  Security
                     40: information moves very fast in cracker circles.  On the other hand,
                     41: our experience is that coding and releasing of proper security fixes
                     42: typically requires about an hour of work -- very fast fix turnaround
                     43: is possible.  Thus we think that full disclosure helps the people who
1.22      deraadt    44: really care about security.<p>
1.15      deraadt    45:
1.12      deraadt    46: Our security auditing team typically has between six and twelve
1.45      deraadt    47: members who continue to search for and fix new security holes.  We
                     48: have been auditing since the summer of 1996.  The process we follow to
                     49: increase security is simply a comprehensive file-by-file analysis of
                     50: every critical software component.  Flaws have been found in just
                     51: about every area of the system.  Entire new classes of security
1.80      espie      52: problems have been found during our audit, and often source code
1.45      deraadt    53: which had been audited earlier needs re-auditing with these new flaws
                     54: in mind.  Code often gets audited multiple times, and by multiple
                     55: people with different auditing skills.<p>
1.12      deraadt    56:
1.31      deraadt    57: Some members of our security auditing team work for
                     58: <a href=http://www.secnet.com>Secure Networks</a>, the company that
1.32      deraadt    59: makes the industry's premier network security scanning software
                     60: package Ballista.
1.31      deraadt    61: This company does a lot of security research, and this fits in well
1.45      deraadt    62: with the OpenBSD stance.  OpenBSD passes Ballista's tests with flying
                     63: colours.<p>
1.31      deraadt    64:
1.34      deraadt    65: Another facet of our security auditing process is its proactiveness.
1.45      deraadt    66: In most cases we have found that the determination of exploitability
                     67: is not an issue.  During our ongoing auditing process we find many
                     68: bugs, and endeavor to fix them even though exploitability is not
                     69: proven.  We fix the bug, and we move on to find other bugs to fix.  We
                     70: have fixed many simple and obvious careless programming errors in code
                     71: and only months later discovered that the problems were in fact
                     72: exploitable.  (Or, more likely someone on
                     73: <a href=http://www.geek-girl.com/bugtraq/index.html>BUGTRAQ</a>
                     74: would report that other operating systems were vulnerable to a `newly
                     75: discovered problem', and then it would be discovered that OpenBSD had
                     76: been fixed in a previous release).  In other cases we have been saved
                     77: from full exploitability of complex step-by-step attacks because we
                     78: had fixed one of the intermediate steps.  An example of where we
                     79: managed such a success is the
1.30      deraadt    80: <a href=http://www.secnet.com/sni-advisories/sni-19.bsd.lpd.advisory.html>
1.35      deraadt    81: lpd advisory from Secure Networks.</a><p>
1.29      deraadt    82:
1.45      deraadt    83: Our proactive auditing process has really paid off.  Statements like
1.35      deraadt    84: ``This problem was fixed in OpenBSD about 6 months ago'' have become
1.45      deraadt    85: commonplace in security forums like
                     86: <a href=http://www.geek-girl.com/bugtraq/index.html>BUGTRAQ</a>.<p>
1.35      deraadt    87:
1.45      deraadt    88: The most intense part of our security auditing happened immediately
1.80      espie      89: before the OpenBSD 2.0 release and during the 2.0-&gt;2.1 transition,
1.45      deraadt    90: over the last third of 1996 and first half of 1997.  Thousands (yes,
                     91: thousands) of security issues were fixed rapidly over this year-long
                     92: period; bugs like the standard buffer overflows, protocol
                     93: implementation weaknesses, information gathering, and filesystem
                     94: races.  Hence most of the security problems that we encountered were
                     95: fixed before our 2.1 release, and then a far smaller number needed
                     96: fixing for our 2.2 release.  We do not find as many problems anymore,
                     97: it is simply a case of diminishing returns.  Recently the security
                     98: problems we find and fix tend to be significantly more obscure or
                     99: complicated.  Still we will persist for a number of reasons:<p>
1.36      deraadt   100:
1.35      deraadt   101: <ul>
1.45      deraadt   102: <li>Occasionally we find a simple problem we missed earlier. Doh!
1.35      deraadt   103: <li>Security is like an arms race; the best attackers will continue
1.45      deraadt   104:        to search for more complicated exploits, so we will too.
                    105: <li>Finding and fixing subtle flaws in complicated software is
                    106:        a lot of fun.
1.35      deraadt   107: </ul>
1.15      deraadt   108:
1.14      deraadt   109: The auditing process is not over yet, and as you can see we continue
1.28      deraadt   110: to find and fix new security flaws.<p>
1.12      deraadt   111:
1.75      deraadt   112: <a name=24></a>
                    113: <p>
                    114: <h3><font color=#e00000><strong>OpenBSD 2.4 Security Advisories</strong></font></h3>
                    115: These are the OpenBSD 2.4 advisories -- all these problems are solved
                    116: in <a href=anoncvs.html>OpenBSD current</a>.  Obviously, all the
                    117: OpenBSD 2.3 advisories listed below are fixed in OpenBSD 2.4.
                    118:
                    119: <ul>
1.91    ! deraadt   120: <li><a href=errata.html#poll>Mar 22, 1999: The nfds argument for poll(2) needs
        !           121:        to be constrained, to avoid kvm starvation (patch included).</a>
        !           122: <li><a href=errata.html#tss>Mar 21, 1999: A change in TSS handling stops
        !           123:        another kernel crash case caused by the <strong>crashme</strong>
        !           124:        program (patch included).</a>
1.89      deraadt   125: <li><a href=errata.html#nlink>Feb 25, 1999: An unbounded increment on the
1.90      deraadt   126:        nlink value in FFS and EXT2FS filesystems can cause a system crash.
1.89      deraadt   127:        (patch included).</a>
1.88      deraadt   128: <li><a href=errata.html#ping>Feb 23, 1999: Yet another buffer overflow
                    129:        existed in ping(8). (patch included).</a>
1.87      deraadt   130: <li><a href=errata.html#ipqrace>Feb 19, 1999: ipintr() had a race in use of
                    131:        the ipq, which could permit an attacker to cause a crash.
                    132:        (patch included).</a>
1.86      deraadt   133: <li><a href=errata.html#accept>Feb 17, 1999: A race condition in the
                    134:        kernel between accept(2) and select(2) could permit an attacker
                    135:        to hang sockets from remote.
                    136:        (patch included).</a>
1.85      deraadt   137: <li><a href=errata.html#maxqueue>Feb 17, 1999: IP fragment assembly can
                    138:        bog the machine excessively and cause problems.
                    139:        (patch included).</a>
1.84      deraadt   140: <li><a href=errata.html#trctrap>Feb 12, 1999: i386 T_TRCTRAP handling and
                    141:        DDB interacted to possibly cause a crash.
                    142:        (patch included).</a>
1.83      deraadt   143: <li><a href=errata.html#rst>Feb 11, 1999: TCP/IP RST handling was sloppy.
                    144:        (patch included).</a>
1.81      deraadt   145: <li><a href=errata.html#bootpd>Nov 27, 1998: There is a remotely exploitable
                    146:        problem in bootpd(8). (patch included).</a>
1.82      deraadt   147: <li><a href=errata.html#termcap>Nov 19, 1998: There is a possibly locally
                    148:        exploitable problem relating to environment variables in termcap
                    149:        and curses. (patch included).</a>
1.78      deraadt   150: <li><a href=errata.html#tcpfix>Nov 13, 1998: There is a remote machine lockup
                    151:        bug in the TCP decoding kernel. (patch included).</a>
1.75      deraadt   152: </ul>
                    153:
1.58      deraadt   154: <a name=23></a>
1.12      deraadt   155: <p>
1.52      deraadt   156: <h3><font color=#e00000><strong>OpenBSD 2.3 Security Advisories</strong></font></h3>
1.73      deraadt   157: These are the OpenBSD 2.3 advisories -- all these problems are solved
                    158: in <a href=anoncvs.html>OpenBSD current</a>.  Obviously, all the
                    159: OpenBSD 2.2 advisories listed below are fixed in OpenBSD 2.3.
1.53      matthieu  160:
                    161: <ul>
1.81      deraadt   162: <li><a href=errata23.html#bootpd>Nov 27, 1998: There is a remotely exploitable
                    163:        problem in bootpd(8). (patch included).</a>
1.78      deraadt   164: <li><a href=errata23.html#tcpfix>Nov 13, 1998: There is a remote machine lockup
                    165:        bug in the TCP decoding kernel. (patch included).</a>
1.76      aaron     166: <li><a href=errata23.html#fdalloc>Jul  2, 1998: setuid and setgid processes
1.72      deraadt   167:        should not be executed with fd slots 0, 1, or 2 free.
                    168:        (patch included).</a>
1.79      deraadt   169: <li><a href=errata23.html#resolver>August 31, 1998: A benign looking resolver buffer overflow bug was re-introduced accidentally (patches included).</a>
1.76      aaron     170: <li><a href=errata23.html#xlib>June 6, 1998: Further problems with the X
1.71      deraadt   171:        libraries (patches included).</a>
1.76      aaron     172: <li><a href=errata23.html#pctr>June  4, 1998: on non-Intel i386 machines, any user
1.72      deraadt   173:        can use pctr(4) to crash the machine.</a>
1.76      aaron     174: <li><a href=errata23.html#kill>May 17, 1998: kill(2) of setuid/setgid target
1.66      deraadt   175:        processes too permissive (4th revision patch included).</a>
1.76      aaron     176: <li><a href=errata23.html#immutable>May 11, 1998: mmap() permits partial bypassing
1.60      deraadt   177:        of immutable and append-only file flags. (patch included).</a>
1.76      aaron     178: <li><a href=errata23.html#xterm-xaw>May  1, 1998: Buffer overflow in xterm and Xaw
1.58      deraadt   179:        (CERT advisory VB-98.04) (patch included).</a>
1.76      aaron     180: <li><a href=errata23.html#ipsec>May  5, 1998: Incorrect handling of IPSEC packets
1.59      deraadt   181:        if IPSEC is enabled (patch included).</a>
1.53      matthieu  182: </ul>
1.9       deraadt   183:
1.58      deraadt   184: <a name=22></a>
1.9       deraadt   185: <p>
1.12      deraadt   186: <h3><font color=#e00000><strong>OpenBSD 2.2 Security Advisories</strong></font></h3>
1.45      deraadt   187: These are the OpenBSD 2.2 advisories.  All these problems are solved
1.55      deraadt   188: in <a href=23.html>OpenBSD 2.3</a>.  Some of these problems
1.45      deraadt   189: still exist in other operating systems.  (The supplied patches are for
                    190: OpenBSD 2.2; they may or may not work on OpenBSD 2.1).
1.9       deraadt   191:
                    192: <ul>
1.72      deraadt   193: <li><a href=errata22.html#ipsec>May  5, 1998: Incorrect handling of IPSEC
                    194:        packets if IPSEC is enabled (patch included).</a>
                    195: <li><a href=errata22.html#xterm-xaw>May  1, 1998: Buffer overflow in xterm
                    196:        and Xaw (CERT advisory VB-98.04) (patch included).</a>
                    197: <li><a href=errata22.html#uucpd>Apr 22, 1998: Buffer overflow in uucpd
                    198:        (patch included).</a>
                    199: <li><a href=errata22.html#rmjob>Apr 22, 1998: Buffer mismanagement in lprm
                    200:        (patch included).</a>
                    201: <li><a href=errata22.html#ping>Mar 31, 1998: Overflow in ping -R (patch included).</a>
                    202: <li><a href=errata22.html#named>Mar 30, 1998: Overflow in named fake-iquery
1.59      deraadt   203:        (patch included).</a>
1.72      deraadt   204: <li><a href=errata22.html#mountd>Mar  2, 1998: Accidental NFS filesystem
                    205:        export (patch included).</a>
                    206: <li><a href=advisories/mmap>Feb 26, 1998: Read-write mmap() flaw.</a>
                    207:        Revision 3 of the patch is available <a href=errata22.html#mmap>here</a>
1.59      deraadt   208: <li><a href=advisories/sourceroute>Feb 19, 1998: Sourcerouted Packet
                    209:        Acceptance.</a>
1.50      deraadt   210:        A patch is available <a href=errata22.html#sourceroute>here</a>.
1.72      deraadt   211: <li><a href=errata22.html#ruserok>Feb 13, 1998: Setuid coredump & Ruserok()
                    212:        flaw (patch included).</a>
                    213: <li><a href=errata22.html#ldso>Feb  9, 1998: MIPS ld.so flaw (patch included).</a>
                    214: <li><a href=errata22.html#f00f>Dec 10, 1997: Intel P5 f00f lockup
1.59      deraadt   215:        (patch included).</a>
1.1       deraadt   216: </ul>
                    217:
1.58      deraadt   218: <a name=21></a>
1.21      deraadt   219: <p>
1.52      deraadt   220: <h3><font color=#e00000><strong>OpenBSD 2.1 Security Advisories</strong></font></h3>
                    221: These are the OpenBSD 2.1 advisories.  All these problems are solved
                    222: in <a href=22.html>OpenBSD 2.2</a>.  Some of these problems still
                    223: exist in other operating systems.  (If you are running OpenBSD 2.1, we
                    224: would strongly recommend an upgrade to the newest release, as this
                    225: patch list only attempts at fixing the most important security
                    226: problems.  In particular, OpenBSD 2.2 fixes numerous localhost
                    227: security problems.  Many of those problems were solved in ways which
                    228: make it hard for us to provide patches).
                    229:
                    230: <ul>
1.72      deraadt   231: <li><a href=advisories/signals>Sep 15, 1997: Deviant Signals (patch included)</a>
1.59      deraadt   232: <li><a href=advisories/rfork>Aug  2, 1997: Rfork() system call flaw
                    233:        (patch included)</a>
                    234: <li><a href=advisories/procfs>Jun 24, 1997: Procfs flaws (patch included)</a>
1.52      deraadt   235: </ul>
1.51      deraadt   236:
                    237: <p>
1.21      deraadt   238: <h3><font color=#e00000><strong>Watching our Security Changes</strong></font></h3>
                    239: Since we take a proactive stance with security, we are continually
                    240: finding and fixing new security problems.  Not all of these problems
1.80      espie     241: get widely reported because (as stated earlier) many of them are not
1.45      deraadt   242: confirmed to be exploitable; many simple bugs we fix do turn out to
                    243: have security consequences we could not predict.  We do not have the
                    244: time resources to make these changes available in the above format.<p>
1.21      deraadt   245:
                    246: Thus there are usually minor security fixes in the current source code
                    247: beyond the previous major OpenBSD release.  We make a limited
1.45      deraadt   248: guarantee that these problems are of minimal impact and unproven
1.44      ian       249: exploitability.  If we discover that a problem definitely matters for
1.45      deraadt   250: security, patches will show up here <strong>VERY</strong> quickly.<p>
1.21      deraadt   251:
1.45      deraadt   252: People who are really concerned with security can do a number of
                    253: things:<p>
1.21      deraadt   254:
                    255: <ul>
                    256: <li>If you understand security issues, watch our
1.27      deraadt   257:        <a href=mail.html>source-changes mailing list</a> and keep an
1.23      deraadt   258:        eye out for things which appear security related.  Since
1.21      deraadt   259:        exploitability is not proven for many of the fixes we make,
                    260:        do not expect the relevant commit message to say "SECURITY FIX!".
                    261:        If a problem is proven and serious, a patch will be available
                    262:        here very shortly after.
                    263: <li>Track our current source code tree, and teach yourself how to do a
1.29      deraadt   264:        complete system build from time to time (read /usr/src/Makefile
                    265:        carefully).  Users can make the assumption that the current
                    266:        source tree always has stronger security than the previous release.
1.45      deraadt   267:        However, building your own system from source code is not trivial;
                    268:        it is nearly 300MB of source code, and problems do occur as we
                    269:        transition between major releases.
1.29      deraadt   270: <li>Install a binary <a href=snapshots.html>snapshot</a> for your
1.80      espie     271:        architecture, which are made available fairly often.  For
1.29      deraadt   272:        instance, an i386 snapshot is typically made available weekly.
1.21      deraadt   273: </ul>
                    274:
1.9       deraadt   275: <p>
1.12      deraadt   276: <h3><font color=#e00000><strong>Other Resources</strong></font></h3>
1.3       deraadt   277: Other security advisories that have (in the past) affected OpenBSD can
1.4       deraadt   278: be found at the <a href=http://www.secnet.com/nav1.html>Secure Networks archive</a>.
1.25      deraadt   279: Some OpenBSD audit team members worked with Secure Networks on discovering
                    280: and solving the problems detailed in some of their security advisories.
1.3       deraadt   281:
1.5       deraadt   282: <p> If you find a new security problem, you can mail it to
1.6       deraadt   283: <a href=mailto:deraadt@openbsd.org>deraadt@openbsd.org</a>.
1.7       deraadt   284: <br>
1.5       deraadt   285: If you wish to PGP encode it (but please only do so if privacy is very
1.27      deraadt   286: urgent, since it is inconvenient) use this <a href=advisories/pgpkey>pgp key</a>.
1.5       deraadt   287:
1.2       deraadt   288: <hr>
1.68      pauls     289: <a href=index.html><img height=24 width=24 src=back.gif border=0 alt=OpenBSD></a>
1.24      deraadt   290: <a href=mailto:www@openbsd.org>www@openbsd.org</a>
                    291: <br>
1.91    ! deraadt   292: <small>$OpenBSD: security.html,v 1.90 1999/03/02 20:04:43 deraadt Exp $</small>
1.1       deraadt   293:
1.24      deraadt   294: </body>
                    295: </html>