Annotation of www/security.html, Revision 1.178
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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
191: <a href=anoncvs.html#using>patch branch</a>.
192:
193: <p>
194: <ul>
1.178 ! aaron 195: <li><a href=errata.html#kernexec>June 15, 2001:
! 196: A race condition in the kernel can lead to local root compromise.</a>
1.177 markus 197: <li><a href=errata.html#sshcookie>June 12, 2001:
198: sshd(8) allows users to delete arbitrary files named "cookies"
199: if X11 forwarding is enabled. X11 forwarding is disabled
200: by default.</a>
1.176 millert 201: <li><a href=errata.html#fts>May 30, 2001:
202: Programs using the fts routines can be tricked into changing
203: into the wrong directory.</a>
1.174 millert 204: <li><a href=errata.html#sendmail>May 29, 2001:
205: Sendmail signal handlers contain unsafe code,
206: leading to numerous race conditions.</a>
1.173 deraadt 207: </ul>
208:
209: <p>
210: <li>
1.152 deraadt 211: <a name=28></a>
212:
213: <h3><font color=#e00000>OpenBSD 2.8 Security Advisories</font></h3>
214: These are the OpenBSD 2.8 advisories -- all these problems are solved
1.154 millert 215: in <a href=anoncvs.html>OpenBSD current</a> and the
216: <a href=anoncvs.html#using>patch branch</a>.
1.152 deraadt 217:
218: <p>
219: <ul>
1.178 ! aaron 220: <li><a href=errata28.html#kernexec>June 15, 2001:
! 221: A race condition in the kernel can lead to local root compromise.</a>
1.176 millert 222: <li><a href=errata28.html#fts>May 30, 2001:
223: Programs using the fts routines can be tricked into changing
224: into the wrong directory.</a>
1.175 millert 225: <li><a href=errata28.html#sendmail>May 29, 2001:
226: Sendmail signal handlers contain unsafe code,
227: leading to numerous race conditions.</a>
1.173 deraadt 228: <li><a href=errata28.html#ipf_frag>Apr 23, 2001:
1.172 ericj 229: IPF contains a serious bug with its handling of fragment cacheing.</a>
1.173 deraadt 230: <li><a href=errata28.html#glob_limit>Apr 23, 2001:
1.172 ericj 231: ftpd(8) contains a potential DoS relating to glob(3).</a>
1.173 deraadt 232: <li><a href=errata28.html#glob>Apr 10, 2001:
1.170 ericj 233: The glob(3) library call contains multiple buffer overflows.</a>
1.173 deraadt 234: <li><a href=errata28.html#readline>Mar 18, 2001:
1.169 millert 235: The readline library creates history files with permissive modes based on the user's umask.</a>
1.173 deraadt 236: <li><a href=errata28.html#ipsec_ah>Mar 2, 2001:
1.167 ericj 237: Insufficient checks in the IPSEC AH IPv4 option handling code can lead to a buffer overrun in the kernel.</a>
1.173 deraadt 238: <li><a href=errata28.html#userldt>Mar 2, 2001:
1.168 horacio 239: The <b>USER_LDT</b> kernel option allows an attacker to gain access to privileged areas of kernel memory.</a>
1.173 deraadt 240: <li><a href=errata28.html#sudo>Feb 22, 2001:
1.171 millert 241: a non-exploitable buffer overflow was fixed in sudo(8).</a>
1.173 deraadt 242: <li><a href=errata28.html#named>Jan 29, 2001:
1.163 jason 243: merge named(8) with ISC BIND 4.9.8-REL, which fixes some buffer vulnerabilities.</a>
1.173 deraadt 244: <li><a href=errata28.html#rnd>Jan 22, 2001:
1.162 jason 245: rnd(4) did not use all of its input when written to.</a>
1.173 deraadt 246: <li><a href=errata28.html#xlock>Dec 22, 2000:
1.159 ericj 247: xlock(1)'s authentication was re-done to authenticate via a named pipe. (patch and new xlock binaries included).</a>
1.173 deraadt 248: <li><a href=errata28.html#procfs>Dec 18, 2000:
1.157 ericj 249: Procfs contains numerous overflows. Procfs is not used by default in OpenBSD. (patch included).</a>
1.173 deraadt 250: <li><a href=errata28.html#kerberos2>Dec 10, 2000:
1.156 deraadt 251: Another problem exists in KerberosIV libraries (patch included).</a>
1.173 deraadt 252: <li><a href=errata28.html#kerberos>Dec 7, 2000:
1.155 deraadt 253: A set of problems in KerberosIV exist (patch included).</a>
1.173 deraadt 254: <li><a href=errata28.html#ftpd>Dec 4, 2000:
1.154 millert 255: A single-byte buffer overflow exists in ftpd (patch included).</a>
1.152 deraadt 256: </ul>
257:
258: <p>
259: <li>
1.124 deraadt 260: <a name=27></a>
261:
262: <h3><font color=#e00000>OpenBSD 2.7 Security Advisories</font></h3>
263: These are the OpenBSD 2.7 advisories -- all these problems are solved
264: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
265: OpenBSD 2.6 advisories listed below are fixed in OpenBSD 2.7.
266:
267: <p>
268: <ul>
1.169 millert 269: <li><a href=errata27.html#readline>Mar 18, 2001:
270: The readline library creates history files with permissive modes based on the user's umask.</a>
271: <li><a href=errata27.html#sudo>Feb 22, 2001:
272: a buffer overflow was fixed in sudo(8).</a>
1.154 millert 273: <li><a href=errata27.html#ftpd>Dec 4, 2000:
274: A single-byte buffer overflow exists in ftpd (patch included).</a>
1.152 deraadt 275: <li><a href=errata27.html#sshforwarding>Nov 10, 2000:
276: Hostile servers can force OpenSSH clients to do agent or X11 forwarding.
277: (patch included)</a>
278: <li><a href=errata27.html#xtrans>Oct 26, 2000:
1.151 matthieu 279: X11 libraries have 2 potential overflows in xtrans code.
280: (patch included)</a>
1.152 deraadt 281: <li><a href=errata27.html#httpd>Oct 18, 2000:
1.150 beck 282: Apache mod_rewrite and mod_vhost_alias modules could expose files
283: on the server in certain configurations if used.
284: (patch included)</a>
1.164 deraadt 285: <li><a href=errata27.html#telnetd>Oct 10, 2000:
1.149 millert 286: The telnet daemon does not strip out the TERMINFO, TERMINFO_DIRS,
287: TERMPATH and TERMCAP environment variables as it should.
288: (patch included)</a>
1.152 deraadt 289: <li><a href=errata27.html#format_strings>Oct 6, 2000:
1.148 millert 290: There are printf-style format string bugs in several privileged
291: programs. (patch included)</a>
1.152 deraadt 292: <li><a href=errata27.html#curses>Oct 6, 2000:
1.147 millert 293: libcurses honored terminal descriptions in the $HOME/.terminfo
294: directory as well as in the TERMCAP environment variable for
295: setuid and setgid applications.
1.146 deraadt 296: (patch included)</a>
1.152 deraadt 297: <li><a href=errata27.html#talkd>Oct 6, 2000:
1.146 deraadt 298: A format string vulnerability exists in talkd(8).
299: (patch included)</a>
1.152 deraadt 300: <li><a href=errata27.html#pw_error>Oct 3, 2000:
1.145 aaron 301: A format string vulnerability exists in the pw_error() function of the
302: libutil library, yielding localhost root through chpass(1).
303: (patch included)</a>
1.152 deraadt 304: <li><a href=errata27.html#ipsec>Sep 18, 2000:
1.144 jason 305: Bad ESP/AH packets could cause a crash under certain conditions.
306: (patch included)</a>
1.152 deraadt 307: <li><a href=errata27.html#xlock>Aug 16, 2000:
1.141 deraadt 308: A format string vulnerability (localhost root) exists in xlock(1).
309: (patch included)</a>
1.152 deraadt 310: <li><a href=errata27.html#X11_libs>July 14, 2000:
1.139 deraadt 311: Various bugs found in X11 libraries have various side effects, almost
312: completely denial of service in OpenBSD.
313: (patch included)</a>
1.152 deraadt 314: <li><a href=errata27.html#ftpd>July 5, 2000:
1.136 deraadt 315: Just like pretty much all the other unix ftp daemons
316: on the planet, ftpd had a remote root hole in it.
317: Luckily, ftpd was not enabled by default.
1.137 deraadt 318: The problem exists if anonymous ftp is enabled.
1.136 deraadt 319: (patch included)</a>
1.152 deraadt 320: <li><a href=errata27.html#mopd>July 5, 2000:
1.136 deraadt 321: Mopd, very rarely used, contained some buffer overflows.
322: (patch included)</a>
1.152 deraadt 323: <li><a href=errata27.html#libedit>June 28, 2000:
1.135 deraadt 324: libedit would check for a <b>.editrc</b> file in the current
325: directory. Not known to be a real security issue, but a patch
326: is available anyways.
327: (patch included)</a>
1.152 deraadt 328: <li><a href=errata27.html#dhclient>June 24, 2000:
1.134 deraadt 329: A serious bug in dhclient(8) could allow strings from a
330: malicious dhcp server to be executed in the shell as root.
331: (patch included)</a>
1.152 deraadt 332: <li><a href=errata27.html#isakmpd>June 9, 2000:
1.133 deraadt 333: A serious bug in isakmpd(8) policy handling wherein
334: policy verification could be completely bypassed in isakmpd.
335: (patch included)</a>
1.152 deraadt 336: <li><a href=errata27.html#uselogin>June 6, 2000:
1.132 deraadt 337: The non-default flag UseLogin in <b>/etc/sshd_config</b> is broken,
338: should not be used, and results in security problems on
339: other operating systems.</a>
1.152 deraadt 340: <li><a href=errata27.html#bridge>May 26, 2000:
1.129 deraadt 341: The bridge(4) <i>learning</i> flag may be bypassed.
1.128 deraadt 342: (patch included)</a>
1.152 deraadt 343: <li><a href=errata27.html#ipf>May 25, 2000:
1.127 kjell 344: Improper use of ipf <i>keep-state</i> rules can result
345: in firewall rules being bypassed. (patch included)</a>
346:
1.124 deraadt 347: </ul>
348:
349: <p>
350: <li>
1.119 deraadt 351: <a name=26></a>
352:
353: <h3><font color=#e00000>OpenBSD 2.6 Security Advisories</font></h3>
354: These are the OpenBSD 2.6 advisories -- all these problems are solved
355: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
356: OpenBSD 2.5 advisories listed below are fixed in OpenBSD 2.6.
357:
358: <p>
359: <ul>
1.130 deraadt 360: <li><a href=errata26.html#semconfig>May 26, 2000:
361: SYSV semaphore support contained an undocumented system call
1.131 deraadt 362: which could wedge semaphore-using processes from exiting. (patch included)</a>
1.127 kjell 363: <li><a href=errata26.html#ipf>May 25, 2000:
364: Improper use of ipf <i>keep-state</i> rules can result
365: in firewall rules being bypassed. (patch included)</a>
1.126 deraadt 366: <li><a href=errata26.html#xlockmore>May 25, 2000:
1.125 deraadt 367: xlockmore has a bug which a localhost attacker can use to gain
368: access to the encrypted root password hash (which is normally
369: encoded using blowfish (see
370: <a href="http://www.openbsd.org/cgi-bin/man.cgi?query=crypt&sektion=3">
371: crypt(3)</a>)
372: (patch included).</a>
1.126 deraadt 373: <li><a href=errata26.html#procfs>Jan 20, 2000:
1.123 deraadt 374: Systems running with procfs enabled and mounted are
375: vulnerable to a very tricky exploit. procfs is not
376: mounted by default.
377: (patch included).</a>
1.126 deraadt 378: <li><a href=errata26.html#ifmedia>Nov 9, 1999:
1.125 deraadt 379: Any user could change interface media configurations, resulting in
380: a localhost denial of service attack.
1.119 deraadt 381: (patch included).</a>
1.126 deraadt 382: <li><a href=errata26.html#sslUSA>Dec 2, 1999:
1.120 deraadt 383: A buffer overflow in the RSAREF code included in the
384: USA version of libssl, is possibly exploitable in
385: httpd, ssh, or isakmpd, if SSL/RSA features are enabled.
1.124 deraadt 386: (patch included).<br></a>
387: <strong>Update:</strong> Turns out that this was not exploitable
388: in any of the software included in OpenBSD 2.6.
1.126 deraadt 389: <li><a href=errata26.html#sendmail>Dec 4, 1999:
1.121 deraadt 390: Sendmail permitted any user to cause a aliases file wrap,
391: thus exposing the system to a race where the aliases file
392: did not exist.
393: (patch included).</a>
1.119 deraadt 394: </ul>
395:
396: <p>
397: <li>
398:
1.93 deraadt 399: <a name=25></a>
1.106 deraadt 400:
1.110 deraadt 401: <h3><font color=#e00000>OpenBSD 2.5 Security Advisories</font></h3>
1.93 deraadt 402: These are the OpenBSD 2.5 advisories -- all these problems are solved
403: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
404: OpenBSD 2.4 advisories listed below are fixed in OpenBSD 2.5.
405:
1.96 deraadt 406: <p>
1.104 deraadt 407: <ul>
1.117 deraadt 408: <li><a href=errata25.html#cron>Aug 30, 1999:
1.103 deraadt 409: In cron(8), make sure argv[] is NULL terminated in the
410: fake popen() and run sendmail as the user, not as root.
411: (patch included).</a>
1.117 deraadt 412: <li><a href=errata25.html#miscfs>Aug 12, 1999: The procfs and fdescfs
1.101 deraadt 413: filesystems had an overrun in their handling of uio_offset
414: in their readdir() routines. (These filesystems are not
415: enabled by default). (patch included).</a>
1.117 deraadt 416: <li><a href=errata25.html#profil>Aug 9, 1999: Stop profiling (see profil(2))
1.100 deraadt 417: when we execve() a new process. (patch included).</a>
1.117 deraadt 418: <li><a href=errata25.html#ipsec_in_use>Aug 6, 1999: Packets that should have
1.98 deraadt 419: been handled by IPsec may be transmitted as cleartext.
420: PF_KEY SA expirations may leak kernel resources.
421: (patch included).</a>
1.117 deraadt 422: <li><a href=errata25.html#rc>Aug 5, 1999: In /etc/rc, use mktemp(1) for
1.97 deraadt 423: motd re-writing and change the find(1) to use -execdir
424: (patch included).</a>
1.117 deraadt 425: <li><a href=errata25.html#chflags>Jul 30, 1999: Do not permit regular
1.95 deraadt 426: users to chflags(2) or fchflags(2) on character or block devices
427: which they may currently be the owner of (patch included).</a>
1.117 deraadt 428: <li><a href=errata25.html#nroff>Jul 27, 1999: Cause groff(1) to be invoked
1.95 deraadt 429: with the -S flag, when called by nroff(1) (patch included).</a>
1.93 deraadt 430: </ul>
431:
1.106 deraadt 432: <p>
433: <li>
1.75 deraadt 434: <a name=24></a>
1.110 deraadt 435: <h3><font color=#e00000>OpenBSD 2.4 Security Advisories</font></h3>
1.75 deraadt 436: These are the OpenBSD 2.4 advisories -- all these problems are solved
437: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
438: OpenBSD 2.3 advisories listed below are fixed in OpenBSD 2.4.
439:
1.96 deraadt 440: <p>
1.75 deraadt 441: <ul>
1.92 deraadt 442: <li><a href=errata24.html#poll>Mar 22, 1999: The nfds argument for poll(2) needs
1.91 deraadt 443: to be constrained, to avoid kvm starvation (patch included).</a>
1.92 deraadt 444: <li><a href=errata24.html#tss>Mar 21, 1999: A change in TSS handling stops
1.91 deraadt 445: another kernel crash case caused by the <strong>crashme</strong>
446: program (patch included).</a>
1.92 deraadt 447: <li><a href=errata24.html#nlink>Feb 25, 1999: An unbounded increment on the
1.90 deraadt 448: nlink value in FFS and EXT2FS filesystems can cause a system crash.
1.89 deraadt 449: (patch included).</a>
1.92 deraadt 450: <li><a href=errata24.html#ping>Feb 23, 1999: Yet another buffer overflow
1.88 deraadt 451: existed in ping(8). (patch included).</a>
1.92 deraadt 452: <li><a href=errata24.html#ipqrace>Feb 19, 1999: ipintr() had a race in use of
1.87 deraadt 453: the ipq, which could permit an attacker to cause a crash.
454: (patch included).</a>
1.92 deraadt 455: <li><a href=errata24.html#accept>Feb 17, 1999: A race condition in the
1.86 deraadt 456: kernel between accept(2) and select(2) could permit an attacker
457: to hang sockets from remote.
458: (patch included).</a>
1.92 deraadt 459: <li><a href=errata24.html#maxqueue>Feb 17, 1999: IP fragment assembly can
1.85 deraadt 460: bog the machine excessively and cause problems.
461: (patch included).</a>
1.92 deraadt 462: <li><a href=errata24.html#trctrap>Feb 12, 1999: i386 T_TRCTRAP handling and
1.84 deraadt 463: DDB interacted to possibly cause a crash.
464: (patch included).</a>
1.92 deraadt 465: <li><a href=errata24.html#rst>Feb 11, 1999: TCP/IP RST handling was sloppy.
1.83 deraadt 466: (patch included).</a>
1.92 deraadt 467: <li><a href=errata24.html#bootpd>Nov 27, 1998: There is a remotely exploitable
1.81 deraadt 468: problem in bootpd(8). (patch included).</a>
1.92 deraadt 469: <li><a href=errata24.html#termcap>Nov 19, 1998: There is a possibly locally
1.82 deraadt 470: exploitable problem relating to environment variables in termcap
471: and curses. (patch included).</a>
1.92 deraadt 472: <li><a href=errata24.html#tcpfix>Nov 13, 1998: There is a remote machine lockup
1.78 deraadt 473: bug in the TCP decoding kernel. (patch included).</a>
1.75 deraadt 474: </ul>
475:
1.106 deraadt 476: <p>
477: <li>
1.58 deraadt 478: <a name=23></a>
1.110 deraadt 479: <h3><font color=#e00000>OpenBSD 2.3 Security Advisories</font></h3>
1.73 deraadt 480: These are the OpenBSD 2.3 advisories -- all these problems are solved
481: in <a href=anoncvs.html>OpenBSD current</a>. Obviously, all the
482: OpenBSD 2.2 advisories listed below are fixed in OpenBSD 2.3.
1.53 matthieu 483:
1.96 deraadt 484: <p>
1.53 matthieu 485: <ul>
1.81 deraadt 486: <li><a href=errata23.html#bootpd>Nov 27, 1998: There is a remotely exploitable
487: problem in bootpd(8). (patch included).</a>
1.78 deraadt 488: <li><a href=errata23.html#tcpfix>Nov 13, 1998: There is a remote machine lockup
489: bug in the TCP decoding kernel. (patch included).</a>
1.76 aaron 490: <li><a href=errata23.html#fdalloc>Jul 2, 1998: setuid and setgid processes
1.72 deraadt 491: should not be executed with fd slots 0, 1, or 2 free.
492: (patch included).</a>
1.79 deraadt 493: <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 494: <li><a href=errata23.html#xlib>June 6, 1998: Further problems with the X
1.71 deraadt 495: libraries (patches included).</a>
1.76 aaron 496: <li><a href=errata23.html#pctr>June 4, 1998: on non-Intel i386 machines, any user
1.72 deraadt 497: can use pctr(4) to crash the machine.</a>
1.76 aaron 498: <li><a href=errata23.html#kill>May 17, 1998: kill(2) of setuid/setgid target
1.66 deraadt 499: processes too permissive (4th revision patch included).</a>
1.76 aaron 500: <li><a href=errata23.html#immutable>May 11, 1998: mmap() permits partial bypassing
1.60 deraadt 501: of immutable and append-only file flags. (patch included).</a>
1.76 aaron 502: <li><a href=errata23.html#xterm-xaw>May 1, 1998: Buffer overflow in xterm and Xaw
1.58 deraadt 503: (CERT advisory VB-98.04) (patch included).</a>
1.76 aaron 504: <li><a href=errata23.html#ipsec>May 5, 1998: Incorrect handling of IPSEC packets
1.59 deraadt 505: if IPSEC is enabled (patch included).</a>
1.53 matthieu 506: </ul>
1.9 deraadt 507:
1.106 deraadt 508: <p>
509: <li>
1.58 deraadt 510: <a name=22></a>
1.110 deraadt 511: <h3><font color=#e00000>OpenBSD 2.2 Security Advisories</font></h3>
1.45 deraadt 512: These are the OpenBSD 2.2 advisories. All these problems are solved
1.55 deraadt 513: in <a href=23.html>OpenBSD 2.3</a>. Some of these problems
1.45 deraadt 514: still exist in other operating systems. (The supplied patches are for
515: OpenBSD 2.2; they may or may not work on OpenBSD 2.1).
1.9 deraadt 516:
1.96 deraadt 517: <p>
1.9 deraadt 518: <ul>
1.72 deraadt 519: <li><a href=errata22.html#ipsec>May 5, 1998: Incorrect handling of IPSEC
520: packets if IPSEC is enabled (patch included).</a>
521: <li><a href=errata22.html#xterm-xaw>May 1, 1998: Buffer overflow in xterm
522: and Xaw (CERT advisory VB-98.04) (patch included).</a>
523: <li><a href=errata22.html#uucpd>Apr 22, 1998: Buffer overflow in uucpd
524: (patch included).</a>
525: <li><a href=errata22.html#rmjob>Apr 22, 1998: Buffer mismanagement in lprm
526: (patch included).</a>
527: <li><a href=errata22.html#ping>Mar 31, 1998: Overflow in ping -R (patch included).</a>
528: <li><a href=errata22.html#named>Mar 30, 1998: Overflow in named fake-iquery
1.59 deraadt 529: (patch included).</a>
1.72 deraadt 530: <li><a href=errata22.html#mountd>Mar 2, 1998: Accidental NFS filesystem
531: export (patch included).</a>
1.112 philen 532: <li><a href="advisories/mmap.txt">Feb 26, 1998: Read-write mmap() flaw.</a>
1.72 deraadt 533: Revision 3 of the patch is available <a href=errata22.html#mmap>here</a>
1.112 philen 534: <li><a href="advisories/sourceroute.txt">Feb 19, 1998: Sourcerouted Packet
1.59 deraadt 535: Acceptance.</a>
1.50 deraadt 536: A patch is available <a href=errata22.html#sourceroute>here</a>.
1.122 rohee 537: <li><a href=errata22.html#ruserok>Feb 13, 1998: Setuid coredump & Ruserok()
1.72 deraadt 538: flaw (patch included).</a>
539: <li><a href=errata22.html#ldso>Feb 9, 1998: MIPS ld.so flaw (patch included).</a>
540: <li><a href=errata22.html#f00f>Dec 10, 1997: Intel P5 f00f lockup
1.59 deraadt 541: (patch included).</a>
1.1 deraadt 542: </ul>
543:
1.106 deraadt 544: <p>
545: <li>
1.58 deraadt 546: <a name=21></a>
1.110 deraadt 547: <h3><font color=#e00000>OpenBSD 2.1 Security Advisories</font></h3>
1.52 deraadt 548: These are the OpenBSD 2.1 advisories. All these problems are solved
549: in <a href=22.html>OpenBSD 2.2</a>. Some of these problems still
550: exist in other operating systems. (If you are running OpenBSD 2.1, we
551: would strongly recommend an upgrade to the newest release, as this
552: patch list only attempts at fixing the most important security
553: problems. In particular, OpenBSD 2.2 fixes numerous localhost
554: security problems. Many of those problems were solved in ways which
555: make it hard for us to provide patches).
556:
1.96 deraadt 557: <p>
1.52 deraadt 558: <ul>
1.112 philen 559: <li><a href="advisories/signals.txt">Sep 15, 1997: Deviant Signals (patch included)</a>
560: <li><a href="advisories/rfork.txt">Aug 2, 1997: Rfork() system call flaw
1.59 deraadt 561: (patch included)</a>
1.112 philen 562: <li><a href="advisories/procfs.txt">Jun 24, 1997: Procfs flaws (patch included)</a>
1.52 deraadt 563: </ul>
1.51 deraadt 564:
1.106 deraadt 565: <p>
566: <li>
567: <a name=20></a>
1.110 deraadt 568: <h3><font color=#e00000>OpenBSD 2.0 Security Advisories</font></h3>
1.99 deraadt 569: These are the OpenBSD 2.0 advisories. All these problems are solved
570: in <a href=21.html>OpenBSD 2.1</a>. Some of these problems still
571: exist in other operating systems. (If you are running OpenBSD 2.0, we
572: commend you for being there back in the old days!, but you're really
573: missing out if you don't install a new version!)
574:
575: <p>
576: <ul>
1.112 philen 577: <li><a href="advisories/res_random.txt">April 22, 1997: Predictable IDs in the
1.99 deraadt 578: resolver (patch included)</a>
579: <li>Many others... if people can hunt them down, please let me know
580: and we'll put them up here.
581: </ul>
582:
1.106 deraadt 583: </dl>
1.51 deraadt 584: <p>
1.106 deraadt 585:
586: <a name=watching></a>
1.110 deraadt 587: <li><h3><font color=#e00000>Watching our Changes</font></h3><p>
1.106 deraadt 588:
1.21 deraadt 589: Since we take a proactive stance with security, we are continually
590: finding and fixing new security problems. Not all of these problems
1.80 espie 591: get widely reported because (as stated earlier) many of them are not
1.45 deraadt 592: confirmed to be exploitable; many simple bugs we fix do turn out to
593: have security consequences we could not predict. We do not have the
594: time resources to make these changes available in the above format.<p>
1.21 deraadt 595:
596: Thus there are usually minor security fixes in the current source code
597: beyond the previous major OpenBSD release. We make a limited
1.45 deraadt 598: guarantee that these problems are of minimal impact and unproven
1.44 ian 599: exploitability. If we discover that a problem definitely matters for
1.45 deraadt 600: security, patches will show up here <strong>VERY</strong> quickly.<p>
1.21 deraadt 601:
1.45 deraadt 602: People who are really concerned with security can do a number of
603: things:<p>
1.21 deraadt 604:
605: <ul>
606: <li>If you understand security issues, watch our
1.27 deraadt 607: <a href=mail.html>source-changes mailing list</a> and keep an
1.23 deraadt 608: eye out for things which appear security related. Since
1.21 deraadt 609: exploitability is not proven for many of the fixes we make,
610: do not expect the relevant commit message to say "SECURITY FIX!".
611: If a problem is proven and serious, a patch will be available
612: here very shortly after.
1.161 horacio 613: <li>In addition to source changes, you can watch our <a href="mail.html">
1.160 ericj 614: security-announce mailing list</a> which will notify you for every
615: security related item that the OpenBSD team deams as a possible threat,
616: and instruct you on how to patch the problem.
1.21 deraadt 617: <li>Track our current source code tree, and teach yourself how to do a
1.29 deraadt 618: complete system build from time to time (read /usr/src/Makefile
619: carefully). Users can make the assumption that the current
620: source tree always has stronger security than the previous release.
1.45 deraadt 621: However, building your own system from source code is not trivial;
622: it is nearly 300MB of source code, and problems do occur as we
623: transition between major releases.
1.115 ericj 624: <li>Install a binary snapshot for your
1.80 espie 625: architecture, which are made available fairly often. For
1.29 deraadt 626: instance, an i386 snapshot is typically made available weekly.
1.21 deraadt 627: </ul>
628:
1.9 deraadt 629: <p>
1.153 jufi 630: <a name=reporting></a>
1.110 deraadt 631: <li><h3><font color=#e00000>Reporting problems</font></h3><p>
1.3 deraadt 632:
1.5 deraadt 633: <p> If you find a new security problem, you can mail it to
1.6 deraadt 634: <a href=mailto:deraadt@openbsd.org>deraadt@openbsd.org</a>.
1.7 deraadt 635: <br>
1.5 deraadt 636: If you wish to PGP encode it (but please only do so if privacy is very
1.112 philen 637: urgent, since it is inconvenient) use this <a href="advisories/pgpkey.txt">pgp key</a>.
1.5 deraadt 638:
1.107 deraadt 639: <p>
640: <a name=papers></a>
1.110 deraadt 641: <li><h3><font color=#e00000>Further Reading</font></h3><p>
1.107 deraadt 642:
643: A number of papers have been written by OpenBSD team members, about security
644: related changes they have done in OpenBSD. The postscript versions of these
1.108 deraadt 645: documents are available as follows.<p>
1.107 deraadt 646:
647: <ul>
1.113 deraadt 648: <li>A Future-Adaptable Password Scheme.<br>
1.118 deraadt 649: <a href=events.html#usenix99>Usenix 1999</a>,
1.153 jufi 650: by <a href=mailto:provos@openbsd.org>Niels Provos</a>,
1.113 deraadt 651: <a href=mailto:dm@openbsd.org>David Mazieres</a>.<br>
1.107 deraadt 652: <a href=papers/bcrypt-paper.ps>paper</a> and
653: <a href=papers/bcrypt-slides.ps>slides</a>.
1.113 deraadt 654: <p>
655: <li>Cryptography in OpenBSD: An Overview.<br>
1.118 deraadt 656: <a href=events.html#usenix99>Usenix 1999</a>,
1.113 deraadt 657: by <a href=mailto:deraadt@openbsd.org>Theo de Raadt</a>,
658: <a href=mailto:niklas@openbsd.org>Niklas Hallqvist</a>,
659: <a href=mailto:art@openbsd.org>Artur Grabowski</a>,
660: <a href=mailto:angelos@openbsd.org>Angelos D. Keromytis</a>,
661: <a href=mailto:provos@openbsd.org>Niels Provos</a>.<br>
1.107 deraadt 662: <a href=papers/crypt-paper.ps>paper</a> and
663: <a href=papers/crypt-slides.ps>slides</a>.
1.113 deraadt 664: <p>
665: <li>strlcpy and strlcat -- consistent, safe, string copy and concatenation.<br>
1.118 deraadt 666: <a href=events.html#usenix99>Usenix 1999</a>,
1.113 deraadt 667: by <a href=mailto:millert@openbsd.org>Todd C. Miller</a>,
668: <a href=mailto:deraadt@openbsd.org>Theo de Raadt</a>.<br>
1.109 deraadt 669: <a href=papers/strlcpy-paper.ps>paper</a> and
670: <a href=papers/strlcpy-slides.ps>slides</a>.
1.113 deraadt 671: <p>
1.118 deraadt 672: <li>Dealing with Public Ethernet Jacks-Switches, Gateways, and Authentication.<br>
673: <a href=events.html#lisa99>LISA 1999</a>,
674: by <a href=mailto:beck@openbsd.org>Bob Beck</a>.<br>
675: <a href=papers/authgw-paper.ps>paper</a> and
676: <a href=papers/authgw-slides.ps>slides</a>.
677: <p>
1.153 jufi 678: <li>Encrypting Virtual Memory<br>
1.142 deraadt 679: <a href=events.html#sec2000>Usenix Security 2000</a>,
680: <a href=mailto:provos@openbsd.org>Niels Provos</a>.<br>
1.143 provos 681: <a href=papers/swapencrypt.ps>paper</a> and
682: <a href=papers/swapencrypt-slides.ps>slides</a>.
1.142 deraadt 683: <p>
1.107 deraadt 684: </ul>
685:
1.106 deraadt 686: </dl>
687:
1.2 deraadt 688: <hr>
1.68 pauls 689: <a href=index.html><img height=24 width=24 src=back.gif border=0 alt=OpenBSD></a>
1.24 deraadt 690: <a href=mailto:www@openbsd.org>www@openbsd.org</a>
691: <br>
1.178 ! aaron 692: <small>$OpenBSD: security.html,v 1.177 2001/06/12 22:33:54 markus Exp $</small>
1.1 deraadt 693:
1.24 deraadt 694: </body>
695: </html>