-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ============================================================================= FreeBSD-SA-06:17.sendmail Security Advisory The FreeBSD Project Topic: Incorrect multipart message handling in Sendmail Category: contrib Module: contrib_sendmail Announced: 2006-06-14 Affects: All FreeBSD releases. Corrected: 2006-06-14 15:58:23 UTC (RELENG_6, 6.1-STABLE) 2006-06-14 15:59:28 UTC (RELENG_6_1, 6.1-RELEASE-p2) 2006-06-14 15:59:37 UTC (RELENG_6_0, 6.0-RELEASE-p9) 2006-06-14 16:00:02 UTC (RELENG_5, 5.5-STABLE) 2006-06-14 16:00:22 UTC (RELENG_5_5, 5.5-RELEASE-p2) 2006-06-14 16:00:42 UTC (RELENG_5_4, 5.4-RELEASE-p16) 2006-06-14 16:00:56 UTC (RELENG_5_3, 5.3-RELEASE-p31) 2006-06-14 16:01:06 UTC (RELENG_4, 4.11-STABLE) 2006-06-14 16:01:21 UTC (RELENG_4_11, 4.11-RELEASE-p19) CVE Name: CVE-2006-1173 For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit . I. Background FreeBSD includes sendmail(8), a general purpose internetwork mail routing facility, as the default Mail Transfer Agent (MTA). II. Problem Description A suitably malformed multipart MIME message can cause sendmail to exceed predefined limits on its stack usage. III. Impact An attacker able to send mail to, or via, a server can cause queued messages on the system to not be delivered, by causing the sendmail process which handles queued messages to crash. Note that this will not stop new messages from entering the queue (either from local processes, or incoming via SMTP). IV. Workaround No workaround is available, but systems which do not receive email from untrusted sources are not vulnerable. V. Solution Perform one of the following: 1) Upgrade your vulnerable system to 4-STABLE, 5-STABLE, or 6-STABLE, or to the RELENG_6_1, RELENG_6_0, RELENG_5_5, RELENG_5_4, RELENG_5_3, or RELENG_4_11 security branch dated after the correction date. 2) To patch your present system: The following patches have been verified to apply to FreeBSD 4.11, 5.3, 5.4, 5.5, 6.0, and 6.1 systems. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. # fetch http://security.FreeBSD.org/patches/SA-06:17/sendmail.patch # fetch http://security.FreeBSD.org/patches/SA-06:17/sendmail.patch.asc b) Execute the following commands as root: # cd /usr/src # patch < /path/to/patch # cd /usr/src/lib/libsm # make obj && make depend && make # cd /usr/src/lib/libsmutil # make obj && make depend && make # cd /usr/src/usr.sbin/sendmail # make obj && make depend && make && make install VI. Correction details The following list contains the revision numbers of each file that was corrected in FreeBSD. Branch Revision Path - ------------------------------------------------------------------------- RELENG_4 src/contrib/sendmail/src/deliver.c 1.1.1.3.2.24 src/contrib/sendmail/src/mime.c 1.1.1.3.2.14 src/contrib/sendmail/src/sendmail.h 1.1.1.4.2.31 RELENG_4_11 src/UPDATING 1.73.2.91.2.19 src/sys/conf/newvers.sh 1.44.2.39.2.22 src/contrib/sendmail/src/deliver.c 1.1.1.3.2.17.2.2 src/contrib/sendmail/src/mime.c 1.1.1.3.2.8.2.2 src/contrib/sendmail/src/sendmail.h 1.1.1.4.2.19.2.2 RELENG_5 src/contrib/sendmail/src/deliver.c 1.1.1.21.2.6 src/contrib/sendmail/src/mime.c 1.1.1.12.2.5 src/contrib/sendmail/src/sendmail.h 1.1.1.23.2.6 RELENG_5_5 src/UPDATING 1.342.2.35.2.1 src/sys/conf/newvers.sh 1.62.2.21.2.3 src/contrib/sendmail/src/deliver.c 1.1.1.21.2.4.2.1 src/contrib/sendmail/src/mime.c 1.1.1.12.2.3.2.1 src/contrib/sendmail/src/sendmail.h 1.1.1.23.2.4.2.1 RELENG_5_4 src/UPDATING 1.342.2.24.2.24 src/sys/conf/newvers.sh 1.62.2.18.2.20 src/contrib/sendmail/src/deliver.c 1.1.1.21.2.1.2.2 src/contrib/sendmail/src/mime.c 1.1.1.12.2.1.2.2 src/contrib/sendmail/src/sendmail.h 1.1.1.23.2.1.2.2 RELENG_5_3 src/UPDATING 1.342.2.13.2.33 src/sys/conf/newvers.sh 1.62.2.15.2.35 src/contrib/sendmail/src/deliver.c 1.1.1.21.4.2 src/contrib/sendmail/src/mime.c 1.1.1.12.4.2 src/contrib/sendmail/src/sendmail.h 1.1.1.23.4.2 RELENG_6 src/contrib/sendmail/src/deliver.c 1.1.1.23.2.3 src/contrib/sendmail/src/mime.c 1.1.1.13.2.3 src/contrib/sendmail/src/sendmail.h 1.1.1.26.2.3 RELENG_6_1 src/UPDATING 1.416.2.22.2.3 src/sys/conf/newvers.sh 1.69.2.11.2.3 src/contrib/sendmail/src/deliver.c 1.1.1.23.2.2.2.1 src/contrib/sendmail/src/mime.c 1.1.1.13.2.2.2.1 src/contrib/sendmail/src/sendmail.h 1.1.1.26.2.2.2.1 RELENG_6_0 src/UPDATING 1.416.2.3.2.13 src/sys/conf/newvers.sh 1.69.2.8.2.9 src/contrib/sendmail/src/deliver.c 1.1.1.23.4.2 src/contrib/sendmail/src/mime.c 1.1.1.13.4.2 src/contrib/sendmail/src/sendmail.h 1.1.1.26.4.2 - ------------------------------------------------------------------------- VII. References http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-1173 The latest revision of this advisory is available at http://security.FreeBSD.org/advisories/FreeBSD-SA-06:17.sendmail.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (FreeBSD) iD8DBQFEkDVJFdaIBMps37IRAqUCAJwKg8UZ2a5oO9XLXpPwgsBi+YdQcACgj2IY D5jN+o1IfjomEK4IIY+xiR8= =t7Wz -----END PGP SIGNATURE-----