Annotation of www/security.html, Revision 1.97
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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>
1.93 deraadt 22: <a href=#25>For 2.5 security advisories, please refer here</a>.<br>
1.56 deraadt 23: <hr>
24:
1.2 deraadt 25: <p>
1.12 deraadt 26: <h3><font color=#e00000><strong>OpenBSD Security Views</strong></font></h3>
1.22 deraadt 27:
1.14 deraadt 28: OpenBSD believes in strong security. Our aspiration is to be NUMBER
1.22 deraadt 29: ONE in the industry for security (if we are not already there). Our
30: open software development model permits us to take a more
31: uncompromising view towards increased security than Sun, SGI, IBM, HP,
32: or other vendors are able to. We can make changes the vendors would
1.27 deraadt 33: not make. Also, since OpenBSD is exported with <a href=crypto.html>
1.45 deraadt 34: cryptography</a>, we are able to take cryptographic approaches towards
35: fixing security problems.<p>
1.18 deraadt 36:
1.45 deraadt 37: Like many readers of the
1.13 deraadt 38: <a href=http://www.geek-girl.com/bugtraq/index.html>
1.18 deraadt 39: BUGTRAQ mailing list</a>,
1.45 deraadt 40: we believe in full disclosure of security problems. Security
41: information moves very fast in cracker circles. On the other hand,
42: our experience is that coding and releasing of proper security fixes
43: typically requires about an hour of work -- very fast fix turnaround
44: is possible. Thus we think that full disclosure helps the people who
1.22 deraadt 45: really care about security.<p>
1.15 deraadt 46:
1.12 deraadt 47: Our security auditing team typically has between six and twelve
1.45 deraadt 48: members who continue to search for and fix new security holes. We
49: have been auditing since the summer of 1996. The process we follow to
50: increase security is simply a comprehensive file-by-file analysis of
51: every critical software component. Flaws have been found in just
52: about every area of the system. Entire new classes of security
1.80 espie 53: problems have been found during our audit, and often source code
1.45 deraadt 54: which had been audited earlier needs re-auditing with these new flaws
55: in mind. Code often gets audited multiple times, and by multiple
56: people with different auditing skills.<p>
1.12 deraadt 57:
1.94 deraadt 58: Some members of our security auditing team worked for Secure Networks,
59: the company that made the industry's premier network security scanning
60: software package Ballista (Secure Networks got purchased by Network
61: Associates, Ballista got renamed to Cybercop Scanner, and well...)
62: That company did a lot of security research, and thus fit in well
1.45 deraadt 63: with the OpenBSD stance. OpenBSD passes Ballista's tests with flying
64: colours.<p>
1.31 deraadt 65:
1.34 deraadt 66: Another facet of our security auditing process is its proactiveness.
1.45 deraadt 67: In most cases we have found that the determination of exploitability
68: is not an issue. During our ongoing auditing process we find many
69: bugs, and endeavor to fix them even though exploitability is not
70: proven. We fix the bug, and we move on to find other bugs to fix. We
71: have fixed many simple and obvious careless programming errors in code
72: and only months later discovered that the problems were in fact
73: exploitable. (Or, more likely someone on
74: <a href=http://www.geek-girl.com/bugtraq/index.html>BUGTRAQ</a>
75: would report that other operating systems were vulnerable to a `newly
76: discovered problem', and then it would be discovered that OpenBSD had
77: been fixed in a previous release). In other cases we have been saved
78: from full exploitability of complex step-by-step attacks because we
79: had fixed one of the intermediate steps. An example of where we
1.94 deraadt 80: managed such a success is the lpd advisory that Secure Networks put out.
81: <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->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:
1.93 deraadt 112: <a name=25></a>
113: <p>
114: <h3><font color=#e00000><strong>OpenBSD 2.5 Security Advisories</strong></font></h3>
115: These are the OpenBSD 2.5 advisories -- all these problems are solved
116: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
117: OpenBSD 2.4 advisories listed below are fixed in OpenBSD 2.5.
118:
1.96 deraadt 119: <p>
1.95 deraadt 120: <ul>
1.97 ! deraadt 121: <li><a href=errata.html#rc>Aug 5, 1999: In /etc/rc, use mktemp(1) for
! 122: motd re-writing and change the find(1) to use -execdir
! 123: (patch included).</a>
1.95 deraadt 124: <li><a href=errata.html#chflags>Jul 30, 1999: Do not permit regular
125: users to chflags(2) or fchflags(2) on character or block devices
126: which they may currently be the owner of (patch included).</a>
127: <li><a href=errata.html#nroff>Jul 27, 1999: Cause groff(1) to be invoked
128: with the -S flag, when called by nroff(1) (patch included).</a>
1.93 deraadt 129: </ul>
130:
1.75 deraadt 131: <a name=24></a>
132: <p>
133: <h3><font color=#e00000><strong>OpenBSD 2.4 Security Advisories</strong></font></h3>
134: These are the OpenBSD 2.4 advisories -- all these problems are solved
135: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
136: OpenBSD 2.3 advisories listed below are fixed in OpenBSD 2.4.
137:
1.96 deraadt 138: <p>
1.75 deraadt 139: <ul>
1.92 deraadt 140: <li><a href=errata24.html#poll>Mar 22, 1999: The nfds argument for poll(2) needs
1.91 deraadt 141: to be constrained, to avoid kvm starvation (patch included).</a>
1.92 deraadt 142: <li><a href=errata24.html#tss>Mar 21, 1999: A change in TSS handling stops
1.91 deraadt 143: another kernel crash case caused by the <strong>crashme</strong>
144: program (patch included).</a>
1.92 deraadt 145: <li><a href=errata24.html#nlink>Feb 25, 1999: An unbounded increment on the
1.90 deraadt 146: nlink value in FFS and EXT2FS filesystems can cause a system crash.
1.89 deraadt 147: (patch included).</a>
1.92 deraadt 148: <li><a href=errata24.html#ping>Feb 23, 1999: Yet another buffer overflow
1.88 deraadt 149: existed in ping(8). (patch included).</a>
1.92 deraadt 150: <li><a href=errata24.html#ipqrace>Feb 19, 1999: ipintr() had a race in use of
1.87 deraadt 151: the ipq, which could permit an attacker to cause a crash.
152: (patch included).</a>
1.92 deraadt 153: <li><a href=errata24.html#accept>Feb 17, 1999: A race condition in the
1.86 deraadt 154: kernel between accept(2) and select(2) could permit an attacker
155: to hang sockets from remote.
156: (patch included).</a>
1.92 deraadt 157: <li><a href=errata24.html#maxqueue>Feb 17, 1999: IP fragment assembly can
1.85 deraadt 158: bog the machine excessively and cause problems.
159: (patch included).</a>
1.92 deraadt 160: <li><a href=errata24.html#trctrap>Feb 12, 1999: i386 T_TRCTRAP handling and
1.84 deraadt 161: DDB interacted to possibly cause a crash.
162: (patch included).</a>
1.92 deraadt 163: <li><a href=errata24.html#rst>Feb 11, 1999: TCP/IP RST handling was sloppy.
1.83 deraadt 164: (patch included).</a>
1.92 deraadt 165: <li><a href=errata24.html#bootpd>Nov 27, 1998: There is a remotely exploitable
1.81 deraadt 166: problem in bootpd(8). (patch included).</a>
1.92 deraadt 167: <li><a href=errata24.html#termcap>Nov 19, 1998: There is a possibly locally
1.82 deraadt 168: exploitable problem relating to environment variables in termcap
169: and curses. (patch included).</a>
1.92 deraadt 170: <li><a href=errata24.html#tcpfix>Nov 13, 1998: There is a remote machine lockup
1.78 deraadt 171: bug in the TCP decoding kernel. (patch included).</a>
1.75 deraadt 172: </ul>
173:
1.58 deraadt 174: <a name=23></a>
1.12 deraadt 175: <p>
1.52 deraadt 176: <h3><font color=#e00000><strong>OpenBSD 2.3 Security Advisories</strong></font></h3>
1.73 deraadt 177: These are the OpenBSD 2.3 advisories -- all these problems are solved
178: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
179: OpenBSD 2.2 advisories listed below are fixed in OpenBSD 2.3.
1.53 matthieu 180:
1.96 deraadt 181: <p>
1.53 matthieu 182: <ul>
1.81 deraadt 183: <li><a href=errata23.html#bootpd>Nov 27, 1998: There is a remotely exploitable
184: problem in bootpd(8). (patch included).</a>
1.78 deraadt 185: <li><a href=errata23.html#tcpfix>Nov 13, 1998: There is a remote machine lockup
186: bug in the TCP decoding kernel. (patch included).</a>
1.76 aaron 187: <li><a href=errata23.html#fdalloc>Jul 2, 1998: setuid and setgid processes
1.72 deraadt 188: should not be executed with fd slots 0, 1, or 2 free.
189: (patch included).</a>
1.79 deraadt 190: <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 191: <li><a href=errata23.html#xlib>June 6, 1998: Further problems with the X
1.71 deraadt 192: libraries (patches included).</a>
1.76 aaron 193: <li><a href=errata23.html#pctr>June 4, 1998: on non-Intel i386 machines, any user
1.72 deraadt 194: can use pctr(4) to crash the machine.</a>
1.76 aaron 195: <li><a href=errata23.html#kill>May 17, 1998: kill(2) of setuid/setgid target
1.66 deraadt 196: processes too permissive (4th revision patch included).</a>
1.76 aaron 197: <li><a href=errata23.html#immutable>May 11, 1998: mmap() permits partial bypassing
1.60 deraadt 198: of immutable and append-only file flags. (patch included).</a>
1.76 aaron 199: <li><a href=errata23.html#xterm-xaw>May 1, 1998: Buffer overflow in xterm and Xaw
1.58 deraadt 200: (CERT advisory VB-98.04) (patch included).</a>
1.76 aaron 201: <li><a href=errata23.html#ipsec>May 5, 1998: Incorrect handling of IPSEC packets
1.59 deraadt 202: if IPSEC is enabled (patch included).</a>
1.53 matthieu 203: </ul>
1.9 deraadt 204:
1.58 deraadt 205: <a name=22></a>
1.9 deraadt 206: <p>
1.12 deraadt 207: <h3><font color=#e00000><strong>OpenBSD 2.2 Security Advisories</strong></font></h3>
1.45 deraadt 208: These are the OpenBSD 2.2 advisories. All these problems are solved
1.55 deraadt 209: in <a href=23.html>OpenBSD 2.3</a>. Some of these problems
1.45 deraadt 210: still exist in other operating systems. (The supplied patches are for
211: OpenBSD 2.2; they may or may not work on OpenBSD 2.1).
1.9 deraadt 212:
1.96 deraadt 213: <p>
1.9 deraadt 214: <ul>
1.72 deraadt 215: <li><a href=errata22.html#ipsec>May 5, 1998: Incorrect handling of IPSEC
216: packets if IPSEC is enabled (patch included).</a>
217: <li><a href=errata22.html#xterm-xaw>May 1, 1998: Buffer overflow in xterm
218: and Xaw (CERT advisory VB-98.04) (patch included).</a>
219: <li><a href=errata22.html#uucpd>Apr 22, 1998: Buffer overflow in uucpd
220: (patch included).</a>
221: <li><a href=errata22.html#rmjob>Apr 22, 1998: Buffer mismanagement in lprm
222: (patch included).</a>
223: <li><a href=errata22.html#ping>Mar 31, 1998: Overflow in ping -R (patch included).</a>
224: <li><a href=errata22.html#named>Mar 30, 1998: Overflow in named fake-iquery
1.59 deraadt 225: (patch included).</a>
1.72 deraadt 226: <li><a href=errata22.html#mountd>Mar 2, 1998: Accidental NFS filesystem
227: export (patch included).</a>
228: <li><a href=advisories/mmap>Feb 26, 1998: Read-write mmap() flaw.</a>
229: Revision 3 of the patch is available <a href=errata22.html#mmap>here</a>
1.59 deraadt 230: <li><a href=advisories/sourceroute>Feb 19, 1998: Sourcerouted Packet
231: Acceptance.</a>
1.50 deraadt 232: A patch is available <a href=errata22.html#sourceroute>here</a>.
1.72 deraadt 233: <li><a href=errata22.html#ruserok>Feb 13, 1998: Setuid coredump & Ruserok()
234: flaw (patch included).</a>
235: <li><a href=errata22.html#ldso>Feb 9, 1998: MIPS ld.so flaw (patch included).</a>
236: <li><a href=errata22.html#f00f>Dec 10, 1997: Intel P5 f00f lockup
1.59 deraadt 237: (patch included).</a>
1.1 deraadt 238: </ul>
239:
1.58 deraadt 240: <a name=21></a>
1.21 deraadt 241: <p>
1.52 deraadt 242: <h3><font color=#e00000><strong>OpenBSD 2.1 Security Advisories</strong></font></h3>
243: These are the OpenBSD 2.1 advisories. All these problems are solved
244: in <a href=22.html>OpenBSD 2.2</a>. Some of these problems still
245: exist in other operating systems. (If you are running OpenBSD 2.1, we
246: would strongly recommend an upgrade to the newest release, as this
247: patch list only attempts at fixing the most important security
248: problems. In particular, OpenBSD 2.2 fixes numerous localhost
249: security problems. Many of those problems were solved in ways which
250: make it hard for us to provide patches).
251:
1.96 deraadt 252: <p>
1.52 deraadt 253: <ul>
1.72 deraadt 254: <li><a href=advisories/signals>Sep 15, 1997: Deviant Signals (patch included)</a>
1.59 deraadt 255: <li><a href=advisories/rfork>Aug 2, 1997: Rfork() system call flaw
256: (patch included)</a>
257: <li><a href=advisories/procfs>Jun 24, 1997: Procfs flaws (patch included)</a>
1.52 deraadt 258: </ul>
1.51 deraadt 259:
260: <p>
1.21 deraadt 261: <h3><font color=#e00000><strong>Watching our Security Changes</strong></font></h3>
262: Since we take a proactive stance with security, we are continually
263: finding and fixing new security problems. Not all of these problems
1.80 espie 264: get widely reported because (as stated earlier) many of them are not
1.45 deraadt 265: confirmed to be exploitable; many simple bugs we fix do turn out to
266: have security consequences we could not predict. We do not have the
267: time resources to make these changes available in the above format.<p>
1.21 deraadt 268:
269: Thus there are usually minor security fixes in the current source code
270: beyond the previous major OpenBSD release. We make a limited
1.45 deraadt 271: guarantee that these problems are of minimal impact and unproven
1.44 ian 272: exploitability. If we discover that a problem definitely matters for
1.45 deraadt 273: security, patches will show up here <strong>VERY</strong> quickly.<p>
1.21 deraadt 274:
1.45 deraadt 275: People who are really concerned with security can do a number of
276: things:<p>
1.21 deraadt 277:
278: <ul>
279: <li>If you understand security issues, watch our
1.27 deraadt 280: <a href=mail.html>source-changes mailing list</a> and keep an
1.23 deraadt 281: eye out for things which appear security related. Since
1.21 deraadt 282: exploitability is not proven for many of the fixes we make,
283: do not expect the relevant commit message to say "SECURITY FIX!".
284: If a problem is proven and serious, a patch will be available
285: here very shortly after.
286: <li>Track our current source code tree, and teach yourself how to do a
1.29 deraadt 287: complete system build from time to time (read /usr/src/Makefile
288: carefully). Users can make the assumption that the current
289: source tree always has stronger security than the previous release.
1.45 deraadt 290: However, building your own system from source code is not trivial;
291: it is nearly 300MB of source code, and problems do occur as we
292: transition between major releases.
1.29 deraadt 293: <li>Install a binary <a href=snapshots.html>snapshot</a> for your
1.80 espie 294: architecture, which are made available fairly often. For
1.29 deraadt 295: instance, an i386 snapshot is typically made available weekly.
1.21 deraadt 296: </ul>
297:
1.9 deraadt 298: <p>
1.12 deraadt 299: <h3><font color=#e00000><strong>Other Resources</strong></font></h3>
1.3 deraadt 300:
1.5 deraadt 301: <p> If you find a new security problem, you can mail it to
1.6 deraadt 302: <a href=mailto:deraadt@openbsd.org>deraadt@openbsd.org</a>.
1.7 deraadt 303: <br>
1.5 deraadt 304: If you wish to PGP encode it (but please only do so if privacy is very
1.27 deraadt 305: urgent, since it is inconvenient) use this <a href=advisories/pgpkey>pgp key</a>.
1.5 deraadt 306:
1.2 deraadt 307: <hr>
1.68 pauls 308: <a href=index.html><img height=24 width=24 src=back.gif border=0 alt=OpenBSD></a>
1.24 deraadt 309: <a href=mailto:www@openbsd.org>www@openbsd.org</a>
310: <br>
1.97 ! deraadt 311: <small>$OpenBSD: security.html,v 1.96 1999/07/30 21:32:05 deraadt Exp $</small>
1.1 deraadt 312:
1.24 deraadt 313: </body>
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