Annotation of www/security.html, Revision 1.180
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1.20 deraadt 4: <title>OpenBSD Security</title>
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1.77 deraadt 14: <img alt="[OpenBSD]" height=30 width=141 SRC="images/smalltitle.gif">
1.106 deraadt 15: <p>
1.110 deraadt 16: <h2><font color=#e00000>Security</font><hr></h2>
1.1 deraadt 17:
1.114 philen 18: <table width="100%">
19: <tr>
20: <td colspan="2">
21: <strong>Index</strong>
22: </td>
23: </tr>
24: <tr>
25: <td valign="top">
1.106 deraadt 26: <a href=#goals>Security goals of the Project</a>.<br>
27: <a href=#disclosure>Full Disclosure policy</a>.<br>
28: <a href=#process>Source code auditing process</a>.<br>
1.111 aaron 29: <a href=#default>"Secure by Default"</a>.<br>
1.106 deraadt 30: <a href=#crypto>Use of Cryptography</a>.<br>
31: <p>
32: <a href=#watching>Watching changes</a>.<br>
33: <a href=#reporting>Reporting security issues</a>.<br>
1.107 deraadt 34: <a href=#papers>Further Reading</a><br>
1.106 deraadt 35: <p>
1.114 philen 36: </td>
37: <td valign="top">
1.173 deraadt 38: <a href="#29">For 2.9 security advisories</a>.<br>
1.152 deraadt 39: <a href="#28">For 2.8 security advisories</a>.<br>
1.124 deraadt 40: <a href="#27">For 2.7 security advisories</a>.<br>
1.119 deraadt 41: <a href="#26">For 2.6 security advisories</a>.<br>
1.114 philen 42: <a href="#25">For 2.5 security advisories</a>.<br>
43: <a href="#24">For 2.4 security advisories</a>.<br>
44: <a href="#23">For 2.3 security advisories</a>.<br>
45: <a href="#22">For 2.2 security advisories</a>.<br>
46: <a href="#21">For 2.1 security advisories</a>.<br>
47: <a href="#20">For 2.0 security advisories</a>.<br>
48: </td>
49: </tr>
50: </table>
1.56 deraadt 51: <hr>
52:
1.106 deraadt 53: <dl>
54: <a name=goals></a>
1.110 deraadt 55: <li><h3><font color=#e00000>Goal</font></h3><p>
1.22 deraadt 56:
1.14 deraadt 57: OpenBSD believes in strong security. Our aspiration is to be NUMBER
1.22 deraadt 58: ONE in the industry for security (if we are not already there). Our
59: open software development model permits us to take a more
60: uncompromising view towards increased security than Sun, SGI, IBM, HP,
61: or other vendors are able to. We can make changes the vendors would
1.27 deraadt 62: not make. Also, since OpenBSD is exported with <a href=crypto.html>
1.45 deraadt 63: cryptography</a>, we are able to take cryptographic approaches towards
64: fixing security problems.<p>
1.18 deraadt 65:
1.106 deraadt 66: <a name=disclosure></a>
1.110 deraadt 67: <li><h3><font color=#e00000>Full Disclosure</font></h3><p>
1.106 deraadt 68:
1.45 deraadt 69: Like many readers of the
1.102 deraadt 70: <a href=http://www.securityfocus.com/bugtraq/archive>
1.18 deraadt 71: BUGTRAQ mailing list</a>,
1.106 deraadt 72: we believe in full disclosure of security problems. In the
73: operating system arena, we were probably the first to embrace
74: the concept. Many vendors, even of free software, still try
75: to hide issues from their users.<p>
76:
77: Security information moves very fast in cracker circles. On the other
78: hand, our experience is that coding and releasing of proper security
79: fixes typically requires about an hour of work -- very fast fix
80: turnaround is possible. Thus we think that full disclosure helps the
81: people who really care about security.<p>
82:
1.153 jufi 83: <a name=process></a>
1.110 deraadt 84: <li><h3><font color=#e00000>Audit Process</font></h3><p>
1.15 deraadt 85:
1.12 deraadt 86: Our security auditing team typically has between six and twelve
1.45 deraadt 87: members who continue to search for and fix new security holes. We
88: have been auditing since the summer of 1996. The process we follow to
89: increase security is simply a comprehensive file-by-file analysis of
1.106 deraadt 90: every critical software component. We are not so much looking for
91: security holes, as we are looking for basic software bugs, and if
1.138 deraadt 92: years later someone discovers the problem used to be a security
1.106 deraadt 93: issue, and we fixed it because it was just a bug, well, all the
94: better. Flaws have been found in just about every area of the system.
95: Entire new classes of security problems have been found during our
96: audit, and often source code which had been audited earlier needs
97: re-auditing with these new flaws in mind. Code often gets audited
98: multiple times, and by multiple people with different auditing
99: skills.<p>
1.12 deraadt 100:
1.94 deraadt 101: Some members of our security auditing team worked for Secure Networks,
102: the company that made the industry's premier network security scanning
103: software package Ballista (Secure Networks got purchased by Network
104: Associates, Ballista got renamed to Cybercop Scanner, and well...)
105: That company did a lot of security research, and thus fit in well
1.106 deraadt 106: with the OpenBSD stance. OpenBSD passed Ballista's tests with flying
107: colours since day 1.<p>
1.31 deraadt 108:
1.34 deraadt 109: Another facet of our security auditing process is its proactiveness.
1.45 deraadt 110: In most cases we have found that the determination of exploitability
111: is not an issue. During our ongoing auditing process we find many
112: bugs, and endeavor to fix them even though exploitability is not
113: proven. We fix the bug, and we move on to find other bugs to fix. We
114: have fixed many simple and obvious careless programming errors in code
115: and only months later discovered that the problems were in fact
116: exploitable. (Or, more likely someone on
1.102 deraadt 117: <a href=http://www.securityfocus.com/bugtraq/archive>BUGTRAQ</a>
1.45 deraadt 118: would report that other operating systems were vulnerable to a `newly
119: discovered problem', and then it would be discovered that OpenBSD had
120: been fixed in a previous release). In other cases we have been saved
121: from full exploitability of complex step-by-step attacks because we
122: had fixed one of the intermediate steps. An example of where we
1.94 deraadt 123: managed such a success is the lpd advisory that Secure Networks put out.
124: <p>
1.29 deraadt 125:
1.110 deraadt 126: <li><h3><font color=#e00000>The Reward</font></h3><p>
1.106 deraadt 127:
1.45 deraadt 128: Our proactive auditing process has really paid off. Statements like
1.35 deraadt 129: ``This problem was fixed in OpenBSD about 6 months ago'' have become
1.45 deraadt 130: commonplace in security forums like
1.102 deraadt 131: <a href=http://www.securityfocus.com/bugtraq/archive>BUGTRAQ</a>.<p>
1.35 deraadt 132:
1.45 deraadt 133: The most intense part of our security auditing happened immediately
1.80 espie 134: before the OpenBSD 2.0 release and during the 2.0->2.1 transition,
1.45 deraadt 135: over the last third of 1996 and first half of 1997. Thousands (yes,
136: thousands) of security issues were fixed rapidly over this year-long
137: period; bugs like the standard buffer overflows, protocol
138: implementation weaknesses, information gathering, and filesystem
139: races. Hence most of the security problems that we encountered were
140: fixed before our 2.1 release, and then a far smaller number needed
141: fixing for our 2.2 release. We do not find as many problems anymore,
142: it is simply a case of diminishing returns. Recently the security
143: problems we find and fix tend to be significantly more obscure or
144: complicated. Still we will persist for a number of reasons:<p>
1.36 deraadt 145:
1.35 deraadt 146: <ul>
1.45 deraadt 147: <li>Occasionally we find a simple problem we missed earlier. Doh!
1.35 deraadt 148: <li>Security is like an arms race; the best attackers will continue
1.45 deraadt 149: to search for more complicated exploits, so we will too.
150: <li>Finding and fixing subtle flaws in complicated software is
151: a lot of fun.
1.35 deraadt 152: </ul>
1.106 deraadt 153: <p>
1.15 deraadt 154:
1.14 deraadt 155: The auditing process is not over yet, and as you can see we continue
1.28 deraadt 156: to find and fix new security flaws.<p>
1.12 deraadt 157:
1.106 deraadt 158: <a name=default></a>
1.110 deraadt 159: <li><h3><font color=#e00000>"Secure by Default"</font></h3><p>
1.106 deraadt 160:
161: To ensure that novice users of OpenBSD do not need to become security
162: experts overnight (a viewpoint which other vendors seem to have), we
163: ship the operating system in a Secure by Default mode. All non-essential
164: services are disabled. As the user/administrator becomes more familiar
165: with the system, he will discover that he has to enable daemons and other
166: parts of the system. During the process of learning how to enable a new
167: service, the novice is more likely to learn of security considerations.<p>
168:
169: This is in stark contrast to the increasing number of systems that
170: ship with NFS, mountd, web servers, and various other services enabled
171: by default, creating instantaneous security problems for their users
172: within minutes after their first install.<p>
173:
1.153 jufi 174: <a name=crypto></a>
1.110 deraadt 175: <li><h3><font color=#e00000>Cryptography</font></h3><p>
1.106 deraadt 176:
177: And of course, since the OpenBSD project is based in Canada, it is possible
178: for us to integrate cryptography. For more information, read the page
1.116 deraadt 179: outlining <a href=crypto.html>what we have done with cryptography</a>.</p>
1.106 deraadt 180:
1.110 deraadt 181: <li><h3><font color=#e00000>Advisories</font></h3><p>
1.106 deraadt 182:
183: <dl>
184:
185: <li>
1.173 deraadt 186: <a name=29></a>
187:
188: <h3><font color=#e00000>OpenBSD 2.9 Security Advisories</font></h3>
189: These are the OpenBSD 2.9 advisories -- all these problems are solved
190: in <a href=anoncvs.html>OpenBSD current</a> and the
1.179 jufi 191: <a href=stable.html>patch branch</a>.
1.173 deraadt 192:
193: <p>
194: <ul>
1.180 ! jason 195: <li><a href=errata.html#nfs>July 30, 2001:
! 196: A kernel buffer overflow in the NFS code can be used to execute
! 197: arbitrary code by users with mount privileges (only root by
! 198: default).
1.178 aaron 199: <li><a href=errata.html#kernexec>June 15, 2001:
200: A race condition in the kernel can lead to local root compromise.</a>
1.177 markus 201: <li><a href=errata.html#sshcookie>June 12, 2001:
202: sshd(8) allows users to delete arbitrary files named "cookies"
203: if X11 forwarding is enabled. X11 forwarding is disabled
204: by default.</a>
1.176 millert 205: <li><a href=errata.html#fts>May 30, 2001:
206: Programs using the fts routines can be tricked into changing
207: into the wrong directory.</a>
1.174 millert 208: <li><a href=errata.html#sendmail>May 29, 2001:
209: Sendmail signal handlers contain unsafe code,
210: leading to numerous race conditions.</a>
1.173 deraadt 211: </ul>
212:
213: <p>
214: <li>
1.152 deraadt 215: <a name=28></a>
216:
217: <h3><font color=#e00000>OpenBSD 2.8 Security Advisories</font></h3>
218: These are the OpenBSD 2.8 advisories -- all these problems are solved
1.154 millert 219: in <a href=anoncvs.html>OpenBSD current</a> and the
1.179 jufi 220: <a href=stable.html>patch branch</a>.
1.152 deraadt 221:
222: <p>
223: <ul>
1.178 aaron 224: <li><a href=errata28.html#kernexec>June 15, 2001:
225: A race condition in the kernel can lead to local root compromise.</a>
1.176 millert 226: <li><a href=errata28.html#fts>May 30, 2001:
227: Programs using the fts routines can be tricked into changing
228: into the wrong directory.</a>
1.175 millert 229: <li><a href=errata28.html#sendmail>May 29, 2001:
230: Sendmail signal handlers contain unsafe code,
231: leading to numerous race conditions.</a>
1.173 deraadt 232: <li><a href=errata28.html#ipf_frag>Apr 23, 2001:
1.172 ericj 233: IPF contains a serious bug with its handling of fragment cacheing.</a>
1.173 deraadt 234: <li><a href=errata28.html#glob_limit>Apr 23, 2001:
1.172 ericj 235: ftpd(8) contains a potential DoS relating to glob(3).</a>
1.173 deraadt 236: <li><a href=errata28.html#glob>Apr 10, 2001:
1.170 ericj 237: The glob(3) library call contains multiple buffer overflows.</a>
1.173 deraadt 238: <li><a href=errata28.html#readline>Mar 18, 2001:
1.169 millert 239: The readline library creates history files with permissive modes based on the user's umask.</a>
1.173 deraadt 240: <li><a href=errata28.html#ipsec_ah>Mar 2, 2001:
1.167 ericj 241: Insufficient checks in the IPSEC AH IPv4 option handling code can lead to a buffer overrun in the kernel.</a>
1.173 deraadt 242: <li><a href=errata28.html#userldt>Mar 2, 2001:
1.168 horacio 243: The <b>USER_LDT</b> kernel option allows an attacker to gain access to privileged areas of kernel memory.</a>
1.173 deraadt 244: <li><a href=errata28.html#sudo>Feb 22, 2001:
1.171 millert 245: a non-exploitable buffer overflow was fixed in sudo(8).</a>
1.173 deraadt 246: <li><a href=errata28.html#named>Jan 29, 2001:
1.163 jason 247: merge named(8) with ISC BIND 4.9.8-REL, which fixes some buffer vulnerabilities.</a>
1.173 deraadt 248: <li><a href=errata28.html#rnd>Jan 22, 2001:
1.162 jason 249: rnd(4) did not use all of its input when written to.</a>
1.173 deraadt 250: <li><a href=errata28.html#xlock>Dec 22, 2000:
1.159 ericj 251: xlock(1)'s authentication was re-done to authenticate via a named pipe. (patch and new xlock binaries included).</a>
1.173 deraadt 252: <li><a href=errata28.html#procfs>Dec 18, 2000:
1.157 ericj 253: Procfs contains numerous overflows. Procfs is not used by default in OpenBSD. (patch included).</a>
1.173 deraadt 254: <li><a href=errata28.html#kerberos2>Dec 10, 2000:
1.156 deraadt 255: Another problem exists in KerberosIV libraries (patch included).</a>
1.173 deraadt 256: <li><a href=errata28.html#kerberos>Dec 7, 2000:
1.155 deraadt 257: A set of problems in KerberosIV exist (patch included).</a>
1.173 deraadt 258: <li><a href=errata28.html#ftpd>Dec 4, 2000:
1.154 millert 259: A single-byte buffer overflow exists in ftpd (patch included).</a>
1.152 deraadt 260: </ul>
261:
262: <p>
263: <li>
1.124 deraadt 264: <a name=27></a>
265:
266: <h3><font color=#e00000>OpenBSD 2.7 Security Advisories</font></h3>
267: These are the OpenBSD 2.7 advisories -- all these problems are solved
268: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
269: OpenBSD 2.6 advisories listed below are fixed in OpenBSD 2.7.
270:
271: <p>
272: <ul>
1.169 millert 273: <li><a href=errata27.html#readline>Mar 18, 2001:
274: The readline library creates history files with permissive modes based on the user's umask.</a>
275: <li><a href=errata27.html#sudo>Feb 22, 2001:
276: a buffer overflow was fixed in sudo(8).</a>
1.154 millert 277: <li><a href=errata27.html#ftpd>Dec 4, 2000:
278: A single-byte buffer overflow exists in ftpd (patch included).</a>
1.152 deraadt 279: <li><a href=errata27.html#sshforwarding>Nov 10, 2000:
280: Hostile servers can force OpenSSH clients to do agent or X11 forwarding.
281: (patch included)</a>
282: <li><a href=errata27.html#xtrans>Oct 26, 2000:
1.151 matthieu 283: X11 libraries have 2 potential overflows in xtrans code.
284: (patch included)</a>
1.152 deraadt 285: <li><a href=errata27.html#httpd>Oct 18, 2000:
1.150 beck 286: Apache mod_rewrite and mod_vhost_alias modules could expose files
287: on the server in certain configurations if used.
288: (patch included)</a>
1.164 deraadt 289: <li><a href=errata27.html#telnetd>Oct 10, 2000:
1.149 millert 290: The telnet daemon does not strip out the TERMINFO, TERMINFO_DIRS,
291: TERMPATH and TERMCAP environment variables as it should.
292: (patch included)</a>
1.152 deraadt 293: <li><a href=errata27.html#format_strings>Oct 6, 2000:
1.148 millert 294: There are printf-style format string bugs in several privileged
295: programs. (patch included)</a>
1.152 deraadt 296: <li><a href=errata27.html#curses>Oct 6, 2000:
1.147 millert 297: libcurses honored terminal descriptions in the $HOME/.terminfo
298: directory as well as in the TERMCAP environment variable for
299: setuid and setgid applications.
1.146 deraadt 300: (patch included)</a>
1.152 deraadt 301: <li><a href=errata27.html#talkd>Oct 6, 2000:
1.146 deraadt 302: A format string vulnerability exists in talkd(8).
303: (patch included)</a>
1.152 deraadt 304: <li><a href=errata27.html#pw_error>Oct 3, 2000:
1.145 aaron 305: A format string vulnerability exists in the pw_error() function of the
306: libutil library, yielding localhost root through chpass(1).
307: (patch included)</a>
1.152 deraadt 308: <li><a href=errata27.html#ipsec>Sep 18, 2000:
1.144 jason 309: Bad ESP/AH packets could cause a crash under certain conditions.
310: (patch included)</a>
1.152 deraadt 311: <li><a href=errata27.html#xlock>Aug 16, 2000:
1.141 deraadt 312: A format string vulnerability (localhost root) exists in xlock(1).
313: (patch included)</a>
1.152 deraadt 314: <li><a href=errata27.html#X11_libs>July 14, 2000:
1.139 deraadt 315: Various bugs found in X11 libraries have various side effects, almost
316: completely denial of service in OpenBSD.
317: (patch included)</a>
1.152 deraadt 318: <li><a href=errata27.html#ftpd>July 5, 2000:
1.136 deraadt 319: Just like pretty much all the other unix ftp daemons
320: on the planet, ftpd had a remote root hole in it.
321: Luckily, ftpd was not enabled by default.
1.137 deraadt 322: The problem exists if anonymous ftp is enabled.
1.136 deraadt 323: (patch included)</a>
1.152 deraadt 324: <li><a href=errata27.html#mopd>July 5, 2000:
1.136 deraadt 325: Mopd, very rarely used, contained some buffer overflows.
326: (patch included)</a>
1.152 deraadt 327: <li><a href=errata27.html#libedit>June 28, 2000:
1.135 deraadt 328: libedit would check for a <b>.editrc</b> file in the current
329: directory. Not known to be a real security issue, but a patch
330: is available anyways.
331: (patch included)</a>
1.152 deraadt 332: <li><a href=errata27.html#dhclient>June 24, 2000:
1.134 deraadt 333: A serious bug in dhclient(8) could allow strings from a
334: malicious dhcp server to be executed in the shell as root.
335: (patch included)</a>
1.152 deraadt 336: <li><a href=errata27.html#isakmpd>June 9, 2000:
1.133 deraadt 337: A serious bug in isakmpd(8) policy handling wherein
338: policy verification could be completely bypassed in isakmpd.
339: (patch included)</a>
1.152 deraadt 340: <li><a href=errata27.html#uselogin>June 6, 2000:
1.132 deraadt 341: The non-default flag UseLogin in <b>/etc/sshd_config</b> is broken,
342: should not be used, and results in security problems on
343: other operating systems.</a>
1.152 deraadt 344: <li><a href=errata27.html#bridge>May 26, 2000:
1.129 deraadt 345: The bridge(4) <i>learning</i> flag may be bypassed.
1.128 deraadt 346: (patch included)</a>
1.152 deraadt 347: <li><a href=errata27.html#ipf>May 25, 2000:
1.127 kjell 348: Improper use of ipf <i>keep-state</i> rules can result
349: in firewall rules being bypassed. (patch included)</a>
350:
1.124 deraadt 351: </ul>
352:
353: <p>
354: <li>
1.119 deraadt 355: <a name=26></a>
356:
357: <h3><font color=#e00000>OpenBSD 2.6 Security Advisories</font></h3>
358: These are the OpenBSD 2.6 advisories -- all these problems are solved
359: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
360: OpenBSD 2.5 advisories listed below are fixed in OpenBSD 2.6.
361:
362: <p>
363: <ul>
1.130 deraadt 364: <li><a href=errata26.html#semconfig>May 26, 2000:
365: SYSV semaphore support contained an undocumented system call
1.131 deraadt 366: which could wedge semaphore-using processes from exiting. (patch included)</a>
1.127 kjell 367: <li><a href=errata26.html#ipf>May 25, 2000:
368: Improper use of ipf <i>keep-state</i> rules can result
369: in firewall rules being bypassed. (patch included)</a>
1.126 deraadt 370: <li><a href=errata26.html#xlockmore>May 25, 2000:
1.125 deraadt 371: xlockmore has a bug which a localhost attacker can use to gain
372: access to the encrypted root password hash (which is normally
373: encoded using blowfish (see
374: <a href="http://www.openbsd.org/cgi-bin/man.cgi?query=crypt&sektion=3">
375: crypt(3)</a>)
376: (patch included).</a>
1.126 deraadt 377: <li><a href=errata26.html#procfs>Jan 20, 2000:
1.123 deraadt 378: Systems running with procfs enabled and mounted are
379: vulnerable to a very tricky exploit. procfs is not
380: mounted by default.
381: (patch included).</a>
1.126 deraadt 382: <li><a href=errata26.html#ifmedia>Nov 9, 1999:
1.125 deraadt 383: Any user could change interface media configurations, resulting in
384: a localhost denial of service attack.
1.119 deraadt 385: (patch included).</a>
1.126 deraadt 386: <li><a href=errata26.html#sslUSA>Dec 2, 1999:
1.120 deraadt 387: A buffer overflow in the RSAREF code included in the
388: USA version of libssl, is possibly exploitable in
389: httpd, ssh, or isakmpd, if SSL/RSA features are enabled.
1.124 deraadt 390: (patch included).<br></a>
391: <strong>Update:</strong> Turns out that this was not exploitable
392: in any of the software included in OpenBSD 2.6.
1.126 deraadt 393: <li><a href=errata26.html#sendmail>Dec 4, 1999:
1.121 deraadt 394: Sendmail permitted any user to cause a aliases file wrap,
395: thus exposing the system to a race where the aliases file
396: did not exist.
397: (patch included).</a>
1.119 deraadt 398: </ul>
399:
400: <p>
401: <li>
402:
1.93 deraadt 403: <a name=25></a>
1.106 deraadt 404:
1.110 deraadt 405: <h3><font color=#e00000>OpenBSD 2.5 Security Advisories</font></h3>
1.93 deraadt 406: These are the OpenBSD 2.5 advisories -- all these problems are solved
407: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
408: OpenBSD 2.4 advisories listed below are fixed in OpenBSD 2.5.
409:
1.96 deraadt 410: <p>
1.104 deraadt 411: <ul>
1.117 deraadt 412: <li><a href=errata25.html#cron>Aug 30, 1999:
1.103 deraadt 413: In cron(8), make sure argv[] is NULL terminated in the
414: fake popen() and run sendmail as the user, not as root.
415: (patch included).</a>
1.117 deraadt 416: <li><a href=errata25.html#miscfs>Aug 12, 1999: The procfs and fdescfs
1.101 deraadt 417: filesystems had an overrun in their handling of uio_offset
418: in their readdir() routines. (These filesystems are not
419: enabled by default). (patch included).</a>
1.117 deraadt 420: <li><a href=errata25.html#profil>Aug 9, 1999: Stop profiling (see profil(2))
1.100 deraadt 421: when we execve() a new process. (patch included).</a>
1.117 deraadt 422: <li><a href=errata25.html#ipsec_in_use>Aug 6, 1999: Packets that should have
1.98 deraadt 423: been handled by IPsec may be transmitted as cleartext.
424: PF_KEY SA expirations may leak kernel resources.
425: (patch included).</a>
1.117 deraadt 426: <li><a href=errata25.html#rc>Aug 5, 1999: In /etc/rc, use mktemp(1) for
1.97 deraadt 427: motd re-writing and change the find(1) to use -execdir
428: (patch included).</a>
1.117 deraadt 429: <li><a href=errata25.html#chflags>Jul 30, 1999: Do not permit regular
1.95 deraadt 430: users to chflags(2) or fchflags(2) on character or block devices
431: which they may currently be the owner of (patch included).</a>
1.117 deraadt 432: <li><a href=errata25.html#nroff>Jul 27, 1999: Cause groff(1) to be invoked
1.95 deraadt 433: with the -S flag, when called by nroff(1) (patch included).</a>
1.93 deraadt 434: </ul>
435:
1.106 deraadt 436: <p>
437: <li>
1.75 deraadt 438: <a name=24></a>
1.110 deraadt 439: <h3><font color=#e00000>OpenBSD 2.4 Security Advisories</font></h3>
1.75 deraadt 440: These are the OpenBSD 2.4 advisories -- all these problems are solved
441: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
442: OpenBSD 2.3 advisories listed below are fixed in OpenBSD 2.4.
443:
1.96 deraadt 444: <p>
1.75 deraadt 445: <ul>
1.92 deraadt 446: <li><a href=errata24.html#poll>Mar 22, 1999: The nfds argument for poll(2) needs
1.91 deraadt 447: to be constrained, to avoid kvm starvation (patch included).</a>
1.92 deraadt 448: <li><a href=errata24.html#tss>Mar 21, 1999: A change in TSS handling stops
1.91 deraadt 449: another kernel crash case caused by the <strong>crashme</strong>
450: program (patch included).</a>
1.92 deraadt 451: <li><a href=errata24.html#nlink>Feb 25, 1999: An unbounded increment on the
1.90 deraadt 452: nlink value in FFS and EXT2FS filesystems can cause a system crash.
1.89 deraadt 453: (patch included).</a>
1.92 deraadt 454: <li><a href=errata24.html#ping>Feb 23, 1999: Yet another buffer overflow
1.88 deraadt 455: existed in ping(8). (patch included).</a>
1.92 deraadt 456: <li><a href=errata24.html#ipqrace>Feb 19, 1999: ipintr() had a race in use of
1.87 deraadt 457: the ipq, which could permit an attacker to cause a crash.
458: (patch included).</a>
1.92 deraadt 459: <li><a href=errata24.html#accept>Feb 17, 1999: A race condition in the
1.86 deraadt 460: kernel between accept(2) and select(2) could permit an attacker
461: to hang sockets from remote.
462: (patch included).</a>
1.92 deraadt 463: <li><a href=errata24.html#maxqueue>Feb 17, 1999: IP fragment assembly can
1.85 deraadt 464: bog the machine excessively and cause problems.
465: (patch included).</a>
1.92 deraadt 466: <li><a href=errata24.html#trctrap>Feb 12, 1999: i386 T_TRCTRAP handling and
1.84 deraadt 467: DDB interacted to possibly cause a crash.
468: (patch included).</a>
1.92 deraadt 469: <li><a href=errata24.html#rst>Feb 11, 1999: TCP/IP RST handling was sloppy.
1.83 deraadt 470: (patch included).</a>
1.92 deraadt 471: <li><a href=errata24.html#bootpd>Nov 27, 1998: There is a remotely exploitable
1.81 deraadt 472: problem in bootpd(8). (patch included).</a>
1.92 deraadt 473: <li><a href=errata24.html#termcap>Nov 19, 1998: There is a possibly locally
1.82 deraadt 474: exploitable problem relating to environment variables in termcap
475: and curses. (patch included).</a>
1.92 deraadt 476: <li><a href=errata24.html#tcpfix>Nov 13, 1998: There is a remote machine lockup
1.78 deraadt 477: bug in the TCP decoding kernel. (patch included).</a>
1.75 deraadt 478: </ul>
479:
1.106 deraadt 480: <p>
481: <li>
1.58 deraadt 482: <a name=23></a>
1.110 deraadt 483: <h3><font color=#e00000>OpenBSD 2.3 Security Advisories</font></h3>
1.73 deraadt 484: These are the OpenBSD 2.3 advisories -- all these problems are solved
485: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
486: OpenBSD 2.2 advisories listed below are fixed in OpenBSD 2.3.
1.53 matthieu 487:
1.96 deraadt 488: <p>
1.53 matthieu 489: <ul>
1.81 deraadt 490: <li><a href=errata23.html#bootpd>Nov 27, 1998: There is a remotely exploitable
491: problem in bootpd(8). (patch included).</a>
1.78 deraadt 492: <li><a href=errata23.html#tcpfix>Nov 13, 1998: There is a remote machine lockup
493: bug in the TCP decoding kernel. (patch included).</a>
1.76 aaron 494: <li><a href=errata23.html#fdalloc>Jul 2, 1998: setuid and setgid processes
1.72 deraadt 495: should not be executed with fd slots 0, 1, or 2 free.
496: (patch included).</a>
1.79 deraadt 497: <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 498: <li><a href=errata23.html#xlib>June 6, 1998: Further problems with the X
1.71 deraadt 499: libraries (patches included).</a>
1.76 aaron 500: <li><a href=errata23.html#pctr>June 4, 1998: on non-Intel i386 machines, any user
1.72 deraadt 501: can use pctr(4) to crash the machine.</a>
1.76 aaron 502: <li><a href=errata23.html#kill>May 17, 1998: kill(2) of setuid/setgid target
1.66 deraadt 503: processes too permissive (4th revision patch included).</a>
1.76 aaron 504: <li><a href=errata23.html#immutable>May 11, 1998: mmap() permits partial bypassing
1.60 deraadt 505: of immutable and append-only file flags. (patch included).</a>
1.76 aaron 506: <li><a href=errata23.html#xterm-xaw>May 1, 1998: Buffer overflow in xterm and Xaw
1.58 deraadt 507: (CERT advisory VB-98.04) (patch included).</a>
1.76 aaron 508: <li><a href=errata23.html#ipsec>May 5, 1998: Incorrect handling of IPSEC packets
1.59 deraadt 509: if IPSEC is enabled (patch included).</a>
1.53 matthieu 510: </ul>
1.9 deraadt 511:
1.106 deraadt 512: <p>
513: <li>
1.58 deraadt 514: <a name=22></a>
1.110 deraadt 515: <h3><font color=#e00000>OpenBSD 2.2 Security Advisories</font></h3>
1.45 deraadt 516: These are the OpenBSD 2.2 advisories. All these problems are solved
1.55 deraadt 517: in <a href=23.html>OpenBSD 2.3</a>. Some of these problems
1.45 deraadt 518: still exist in other operating systems. (The supplied patches are for
519: OpenBSD 2.2; they may or may not work on OpenBSD 2.1).
1.9 deraadt 520:
1.96 deraadt 521: <p>
1.9 deraadt 522: <ul>
1.72 deraadt 523: <li><a href=errata22.html#ipsec>May 5, 1998: Incorrect handling of IPSEC
524: packets if IPSEC is enabled (patch included).</a>
525: <li><a href=errata22.html#xterm-xaw>May 1, 1998: Buffer overflow in xterm
526: and Xaw (CERT advisory VB-98.04) (patch included).</a>
527: <li><a href=errata22.html#uucpd>Apr 22, 1998: Buffer overflow in uucpd
528: (patch included).</a>
529: <li><a href=errata22.html#rmjob>Apr 22, 1998: Buffer mismanagement in lprm
530: (patch included).</a>
531: <li><a href=errata22.html#ping>Mar 31, 1998: Overflow in ping -R (patch included).</a>
532: <li><a href=errata22.html#named>Mar 30, 1998: Overflow in named fake-iquery
1.59 deraadt 533: (patch included).</a>
1.72 deraadt 534: <li><a href=errata22.html#mountd>Mar 2, 1998: Accidental NFS filesystem
535: export (patch included).</a>
1.112 philen 536: <li><a href="advisories/mmap.txt">Feb 26, 1998: Read-write mmap() flaw.</a>
1.72 deraadt 537: Revision 3 of the patch is available <a href=errata22.html#mmap>here</a>
1.112 philen 538: <li><a href="advisories/sourceroute.txt">Feb 19, 1998: Sourcerouted Packet
1.59 deraadt 539: Acceptance.</a>
1.50 deraadt 540: A patch is available <a href=errata22.html#sourceroute>here</a>.
1.122 rohee 541: <li><a href=errata22.html#ruserok>Feb 13, 1998: Setuid coredump & Ruserok()
1.72 deraadt 542: flaw (patch included).</a>
543: <li><a href=errata22.html#ldso>Feb 9, 1998: MIPS ld.so flaw (patch included).</a>
544: <li><a href=errata22.html#f00f>Dec 10, 1997: Intel P5 f00f lockup
1.59 deraadt 545: (patch included).</a>
1.1 deraadt 546: </ul>
547:
1.106 deraadt 548: <p>
549: <li>
1.58 deraadt 550: <a name=21></a>
1.110 deraadt 551: <h3><font color=#e00000>OpenBSD 2.1 Security Advisories</font></h3>
1.52 deraadt 552: These are the OpenBSD 2.1 advisories. All these problems are solved
553: in <a href=22.html>OpenBSD 2.2</a>. Some of these problems still
554: exist in other operating systems. (If you are running OpenBSD 2.1, we
555: would strongly recommend an upgrade to the newest release, as this
556: patch list only attempts at fixing the most important security
557: problems. In particular, OpenBSD 2.2 fixes numerous localhost
558: security problems. Many of those problems were solved in ways which
559: make it hard for us to provide patches).
560:
1.96 deraadt 561: <p>
1.52 deraadt 562: <ul>
1.112 philen 563: <li><a href="advisories/signals.txt">Sep 15, 1997: Deviant Signals (patch included)</a>
564: <li><a href="advisories/rfork.txt">Aug 2, 1997: Rfork() system call flaw
1.59 deraadt 565: (patch included)</a>
1.112 philen 566: <li><a href="advisories/procfs.txt">Jun 24, 1997: Procfs flaws (patch included)</a>
1.52 deraadt 567: </ul>
1.51 deraadt 568:
1.106 deraadt 569: <p>
570: <li>
571: <a name=20></a>
1.110 deraadt 572: <h3><font color=#e00000>OpenBSD 2.0 Security Advisories</font></h3>
1.99 deraadt 573: These are the OpenBSD 2.0 advisories. All these problems are solved
574: in <a href=21.html>OpenBSD 2.1</a>. Some of these problems still
575: exist in other operating systems. (If you are running OpenBSD 2.0, we
576: commend you for being there back in the old days!, but you're really
577: missing out if you don't install a new version!)
578:
579: <p>
580: <ul>
1.112 philen 581: <li><a href="advisories/res_random.txt">April 22, 1997: Predictable IDs in the
1.99 deraadt 582: resolver (patch included)</a>
583: <li>Many others... if people can hunt them down, please let me know
584: and we'll put them up here.
585: </ul>
586:
1.106 deraadt 587: </dl>
1.51 deraadt 588: <p>
1.106 deraadt 589:
590: <a name=watching></a>
1.110 deraadt 591: <li><h3><font color=#e00000>Watching our Changes</font></h3><p>
1.106 deraadt 592:
1.21 deraadt 593: Since we take a proactive stance with security, we are continually
594: finding and fixing new security problems. Not all of these problems
1.80 espie 595: get widely reported because (as stated earlier) many of them are not
1.45 deraadt 596: confirmed to be exploitable; many simple bugs we fix do turn out to
597: have security consequences we could not predict. We do not have the
598: time resources to make these changes available in the above format.<p>
1.21 deraadt 599:
600: Thus there are usually minor security fixes in the current source code
601: beyond the previous major OpenBSD release. We make a limited
1.45 deraadt 602: guarantee that these problems are of minimal impact and unproven
1.44 ian 603: exploitability. If we discover that a problem definitely matters for
1.45 deraadt 604: security, patches will show up here <strong>VERY</strong> quickly.<p>
1.21 deraadt 605:
1.45 deraadt 606: People who are really concerned with security can do a number of
607: things:<p>
1.21 deraadt 608:
609: <ul>
610: <li>If you understand security issues, watch our
1.27 deraadt 611: <a href=mail.html>source-changes mailing list</a> and keep an
1.23 deraadt 612: eye out for things which appear security related. Since
1.21 deraadt 613: exploitability is not proven for many of the fixes we make,
614: do not expect the relevant commit message to say "SECURITY FIX!".
615: If a problem is proven and serious, a patch will be available
616: here very shortly after.
1.161 horacio 617: <li>In addition to source changes, you can watch our <a href="mail.html">
1.160 ericj 618: security-announce mailing list</a> which will notify you for every
619: security related item that the OpenBSD team deams as a possible threat,
620: and instruct you on how to patch the problem.
1.21 deraadt 621: <li>Track our current source code tree, and teach yourself how to do a
1.29 deraadt 622: complete system build from time to time (read /usr/src/Makefile
623: carefully). Users can make the assumption that the current
624: source tree always has stronger security than the previous release.
1.45 deraadt 625: However, building your own system from source code is not trivial;
626: it is nearly 300MB of source code, and problems do occur as we
627: transition between major releases.
1.115 ericj 628: <li>Install a binary snapshot for your
1.80 espie 629: architecture, which are made available fairly often. For
1.29 deraadt 630: instance, an i386 snapshot is typically made available weekly.
1.21 deraadt 631: </ul>
632:
1.9 deraadt 633: <p>
1.153 jufi 634: <a name=reporting></a>
1.110 deraadt 635: <li><h3><font color=#e00000>Reporting problems</font></h3><p>
1.3 deraadt 636:
1.5 deraadt 637: <p> If you find a new security problem, you can mail it to
1.6 deraadt 638: <a href=mailto:deraadt@openbsd.org>deraadt@openbsd.org</a>.
1.7 deraadt 639: <br>
1.5 deraadt 640: If you wish to PGP encode it (but please only do so if privacy is very
1.112 philen 641: urgent, since it is inconvenient) use this <a href="advisories/pgpkey.txt">pgp key</a>.
1.5 deraadt 642:
1.107 deraadt 643: <p>
644: <a name=papers></a>
1.110 deraadt 645: <li><h3><font color=#e00000>Further Reading</font></h3><p>
1.107 deraadt 646:
647: A number of papers have been written by OpenBSD team members, about security
648: related changes they have done in OpenBSD. The postscript versions of these
1.108 deraadt 649: documents are available as follows.<p>
1.107 deraadt 650:
651: <ul>
1.113 deraadt 652: <li>A Future-Adaptable Password Scheme.<br>
1.118 deraadt 653: <a href=events.html#usenix99>Usenix 1999</a>,
1.153 jufi 654: by <a href=mailto:provos@openbsd.org>Niels Provos</a>,
1.113 deraadt 655: <a href=mailto:dm@openbsd.org>David Mazieres</a>.<br>
1.107 deraadt 656: <a href=papers/bcrypt-paper.ps>paper</a> and
657: <a href=papers/bcrypt-slides.ps>slides</a>.
1.113 deraadt 658: <p>
659: <li>Cryptography in OpenBSD: An Overview.<br>
1.118 deraadt 660: <a href=events.html#usenix99>Usenix 1999</a>,
1.113 deraadt 661: by <a href=mailto:deraadt@openbsd.org>Theo de Raadt</a>,
662: <a href=mailto:niklas@openbsd.org>Niklas Hallqvist</a>,
663: <a href=mailto:art@openbsd.org>Artur Grabowski</a>,
664: <a href=mailto:angelos@openbsd.org>Angelos D. Keromytis</a>,
665: <a href=mailto:provos@openbsd.org>Niels Provos</a>.<br>
1.107 deraadt 666: <a href=papers/crypt-paper.ps>paper</a> and
667: <a href=papers/crypt-slides.ps>slides</a>.
1.113 deraadt 668: <p>
669: <li>strlcpy and strlcat -- consistent, safe, string copy and concatenation.<br>
1.118 deraadt 670: <a href=events.html#usenix99>Usenix 1999</a>,
1.113 deraadt 671: by <a href=mailto:millert@openbsd.org>Todd C. Miller</a>,
672: <a href=mailto:deraadt@openbsd.org>Theo de Raadt</a>.<br>
1.109 deraadt 673: <a href=papers/strlcpy-paper.ps>paper</a> and
674: <a href=papers/strlcpy-slides.ps>slides</a>.
1.113 deraadt 675: <p>
1.118 deraadt 676: <li>Dealing with Public Ethernet Jacks-Switches, Gateways, and Authentication.<br>
677: <a href=events.html#lisa99>LISA 1999</a>,
678: by <a href=mailto:beck@openbsd.org>Bob Beck</a>.<br>
679: <a href=papers/authgw-paper.ps>paper</a> and
680: <a href=papers/authgw-slides.ps>slides</a>.
681: <p>
1.153 jufi 682: <li>Encrypting Virtual Memory<br>
1.142 deraadt 683: <a href=events.html#sec2000>Usenix Security 2000</a>,
684: <a href=mailto:provos@openbsd.org>Niels Provos</a>.<br>
1.143 provos 685: <a href=papers/swapencrypt.ps>paper</a> and
686: <a href=papers/swapencrypt-slides.ps>slides</a>.
1.142 deraadt 687: <p>
1.107 deraadt 688: </ul>
689:
1.106 deraadt 690: </dl>
691:
1.2 deraadt 692: <hr>
1.68 pauls 693: <a href=index.html><img height=24 width=24 src=back.gif border=0 alt=OpenBSD></a>
1.24 deraadt 694: <a href=mailto:www@openbsd.org>www@openbsd.org</a>
695: <br>
1.180 ! jason 696: <small>$OpenBSD: security.html,v 1.179 2001/07/02 20:53:17 jufi Exp $</small>
1.1 deraadt 697:
1.24 deraadt 698: </body>
699: </html>