05 October 2006
Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2006.0709 -- [Win][UNIX/Linux] OpenSSH 4.4 released 5 October 2006 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: OpenSSH Publisher: OpenSSH Operating System: UNIX variants (UNIX, Linux, OSX) Windows Impact: Denial of Service Execute Arbitrary Code/Commands Reduced Security Access: Remote/Unauthenticated CVE Names: CVE-2006-5051 CVE-2006-4924 Revision History: October 5 2006: Added CVE-2006-5051 and CVE-2006-4924 September 28 2006: Initial Release - --------------------------BEGIN INCLUDED TEXT-------------------- OpenSSH 4.4 has just been released. It will be available from the mirrors listed at http://www.openssh.com/ shortly. OpenSSH is a 100% complete SSH protocol version 1.3, 1.5 and 2.0 implementation and includes sftp client and server support. Once again, we would like to thank the OpenSSH community for their continued support of the project, especially those who contributed code or patches, reported bugs, tested snapshots and purchased T-shirts or posters. T-shirt, poster and CD sales directly support the project. Pictures and more information can be found at: http://www.openbsd.org/tshirts.html and http://www.openbsd.org/orders.html For international orders use http://https.openbsd.org/cgi-bin/order and for European orders, use http://https.openbsd.org/cgi-bin/order.eu Changes since OpenSSH 4.3: ============================ Security bugs resolved in this release: * Fix a pre-authentication denial of service found by Tavis Ormandy, that would cause sshd(8) to spin until the login grace time expired. * Fix an unsafe signal hander reported by Mark Dowd. The signal handler was vulnerable to a race condition that could be exploited to perform a pre-authentication denial of service. On portable OpenSSH, this vulnerability could theoretically lead to pre-authentication remote code execution if GSSAPI authentication is enabled, but the likelihood of successful exploitation appears remote. * On portable OpenSSH, fix a GSSAPI authentication abort that could be used to determine the validity of usernames on some platforms. This release includes the following new functionality and fixes: * Implemented conditional configuration in sshd_config(5) using the "Match" directive. This allows some configuration options to be selectively overridden if specific criteria (based on user, group, hostname and/or address) are met. So far a useful subset of post- authentication options are supported and more are expected to be added in future releases. * Add support for Diffie-Hellman group exchange key agreement with a final hash of SHA256. * Added a "ForceCommand" directive to sshd_config(5). Similar to the command="..." option accepted in ~/.ssh/authorized_keys, this forces the execution of the specified command regardless of what the user requested. This is very useful in conjunction with the new "Match" option. * Add a "PermitOpen" directive to sshd_config(5). This mirrors the permitopen="..." authorized_keys option, allowing fine-grained control over the port-forwardings that a user is allowed to establish. * Add optional logging of transactions to sftp-server(8). * ssh(1) will now record port numbers for hosts stored in ~/.ssh/authorized_keys when a non-standard port has been requested. * Add an "ExitOnForwardFailure" option to cause ssh(1) to exit (with a non-zero exit code) when requested port forwardings could not be established. * Extend sshd_config(5) "SubSystem" declarations to allow the specification of command-line arguments. * Replacement of all integer overflow susceptible invocations of malloc(3) and realloc(3) with overflow-checking equivalents. * Many manpage fixes and improvements * New portable OpenSSH-specific features: - Add optional support for SELinux, controlled using the --with-selinux configure option (experimental) - Add optional support for Solaris process contracts, enabled using the --with-solaris-contracts configure option (experimental) This option will also include SMF metadata in Solaris packages built using the "make package" target - Add optional support for OpenSSL hardware accelerators (engines), enabled using the --with-ssl-engine configure option. * Bugs from http://bugzilla.mindrot.org fixed: #482 - readconf doesn't accept paths with spaces in them. #906 - syslog messages from sshd [net] lost. #975 - Kerberos authentication timing can leak information about account validity. #981 - Flow stop in SSH2. #1102 - C program 'write' with zero length hangs. #1129 - sshd hangs for command-only invocations due to fork/child signals. #1131 - error "buffer_append_space:alloc not supported" #1138 - Passphrase asked for (but ignored) if key file permissions too liberal.. #1156 - Closes connection after C-c is pressed on QNX. #1157 - ssh-keygen doesn't handle DOS line breaks. #1159 - %u and %h not handled in IdentityFile. #1161 - scp -r fails. #1162 - Inappropriate sequence of syslog messages. #1166 - openssh-4.3p1 has some issues compiling. #1171 - configure can't always figure out LLONG_MAX.. #1173 - scp reports lost connection for very large files. #1177 - Incorrect sshrc file location in Makefile.in. #1179 - sshd incorrectly rejects connections due to IP options. #1181 - configure should detect when openssl-0.9.8x needs -ldl. #1186 - ssh tries multiple times to open unprotected keys. #1188 - keyboard-interactive should not allow retry after pam_acct_mgmt fails. #1193 - Open ssh will not allow changing of passwords on usernames greater than 8 characters.. #1201 - Bind address information is not specified in command line help messages. #1203 - configure.ac is missing an open [. #1207 - sshd does not clear unsuccessful login count on non-interactive logins. #1218 - GSSAPI client code permits SPNEGO usage. #1221 - Banner only suppressed at log level = QUIET (used to be at log level < INFO). * Fixes to memory and file descriptor leaks reported by the Coverity static analysis tool * Fixes to inconsistent pointer checks reported by the Stanford SATURN tool Thanks to everyone who has contributed patches, reported bugs and tested releases. Checksums: ========== - - SHA1 (openssh-4.4.tar.gz) = 2294b5e5a591420aa05ff607c1890ab622ace878 - - SHA1 (openssh-4.4p1.tar.gz) = 6a52b1dee1c2c9862923c0008d201d98a7fd9d6c Reporting Bugs: =============== - - please read http://www.openssh.com/report.html and http://bugzilla.mindrot.org/ OpenSSH is brought to you by Markus Friedl, Niels Provos, Theo de Raadt, Kevin Steves, Damien Miller, Darren Tucker, Jason McIntyre, Tim Rice and Ben Lindstrom. - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to firstname.lastname@example.org and we will forward your request to the appropriate person. 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If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: http://www.auscert.org.au/render.html?cid=1980 If you believe that your computer system has been compromised or attacked in any way, we encourage you to let us know by completing the secure National IT Incident Reporting Form at: http://www.auscert.org.au/render.html?it=3192 =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: email@example.com Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQCVAwUBRSSH5yh9+71yA2DNAQL7xgP/SPzSqAvg6DIZ+MvblenbdZ7sKTs3ypoY QEf/U9ainAnsJvk2CwBRSLeXFH/j1iyFt7jonJFqtB7hXXWD2NbUPfsEylijuyvo ZO7oSvJQLcctB67sTFd43y7armXlvxfOL+PAYLqplR1i8DeeVfOgAL9pMD3zlfZ9 VSRZFOXB7Ng= =GfHz -----END PGP SIGNATURE-----