-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ============================================================================= FreeBSD-SA-03:13.sendmail Security Advisory The FreeBSD Project Topic: a third sendmail header parsing buffer overflow Category: contrib Module: contrib_sendmail Announced: 2003-09-17 Credits: Michal Zalewski Todd C. Miller Affects: All releases of FreeBSD FreeBSD 4-STABLE prior to the correction date Corrected: 2003-09-17 15:18:20 UTC (RELENG_4, 4.9-PRERELEASE) 2003-09-17 20:19:00 UTC (RELENG_5_1, 5.1-RELEASE-p5) 2003-09-17 20:19:22 UTC (RELENG_5_0, 5.0-RELEASE-p14) 2003-09-17 20:19:52 UTC (RELENG_4_8, 4.8-RELEASE-p7) 2003-09-17 20:20:08 UTC (RELENG_4_7, 4.7-RELEASE-p17) 2003-09-17 20:20:31 UTC (RELENG_4_6, 4.6-RELEASE-p20) 2003-09-17 20:20:54 UTC (RELENG_4_5, 4.5-RELEASE-p32) 2003-09-17 20:21:15 UTC (RELENG_4_4, 4.4-RELEASE-p42) 2003-09-17 20:21:40 UTC (RELENG_4_3, 4.3-RELEASE-p38) 2003-09-17 20:22:03 UTC (RELENG_3) FreeBSD only: NO I. Background FreeBSD includes sendmail(8), a general purpose internetwork mail routing facility, as the default Mail Transfer Agent (MTA). II. Problem Description A buffer overflow that may occur during header parsing was identified. NOTE WELL: This issue is distinct from the issue described in `FreeBSD-SA-03:04.sendmail' and `FreeBSD-SA-03:07.sendmail', although the impact is very similar. III. Impact An attacker could create a specially crafted message that may cause sendmail to execute arbitrary code with the privileges of the user running sendmail, typically root. The malicious message might be handled (and the vulnerability triggered) by the initial sendmail MTA, by any relaying sendmail MTA, or by the delivering sendmail process. IV. Workaround Disable sendmail by executing the following commands as root: # sh /etc/rc.sendmail stop # chmod 0 /usr/libexec/sendmail/sendmail Be sure that sendmail is not restarted when the system is restarted by adding the following line to the end of /etc/rc.conf: sendmail_enable="NO" sendmail_submit_enable="NO" sendmail_outbound_enable="NO" V. Solution Do one of the following: 1) Upgrade your vulnerable system to 4-STABLE; or to the RELENG_5_1, RELENG_4_8, or RELENG_4_7 security branch dated after the correction date. 2) To patch your present system: The following patch has been verified to apply to FreeBSD 5.1, 4.8, and 4.7 systems. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:13/sendmail.patch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/patches/SA-03:13/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 c) Restart sendmail. Execute the following command as root. # /bin/sh /etc/rc.sendmail restart 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/parseaddr.c 1.1.1.2.6.14 RELENG_5_1 src/UPDATING 1.251.2.6 src/contrib/sendmail/src/parseaddr.c 1.1.1.17.2.1 src/contrib/sendmail/src/version.c 1.1.1.19.2.1 src/sys/conf/newvers.sh 1.50.2.7 RELENG_5_0 src/UPDATING 1.229.2.20 src/contrib/sendmail/src/parseaddr.c 1.1.1.14.2.3 src/contrib/sendmail/src/version.c 1.1.1.16.2.2 src/sys/conf/newvers.sh 1.48.2.15 RELENG_4_8 src/UPDATING 1.73.2.80.2.9 src/contrib/sendmail/src/parseaddr.c 1.1.1.2.6.12.2.2 src/contrib/sendmail/src/version.c 1.1.1.3.2.14.2.2 src/sys/conf/newvers.sh 1.44.2.29.2.8 RELENG_4_7 src/UPDATING 1.73.2.74.2.20 src/contrib/sendmail/src/parseaddr.c 1.1.1.2.6.10.2.3 src/contrib/sendmail/src/version.c 1.1.1.3.2.12.2.2 src/sys/conf/newvers.sh 1.44.2.26.2.19 RELENG_4_6 src/UPDATING 1.73.2.68.2.48 src/contrib/sendmail/src/parseaddr.c 1.1.1.2.6.8.2.3 src/contrib/sendmail/src/version.c 1.1.1.3.2.9.2.2 src/sys/conf/newvers.sh 1.44.2.23.2.37 RELENG_4_5 src/UPDATING 1.73.2.50.2.49 src/contrib/sendmail/src/parseaddr.c 1.1.1.2.6.6.4.3 src/contrib/sendmail/src/version.c 1.1.1.3.2.7.4.2 src/sys/conf/newvers.sh 1.44.2.20.2.33 RELENG_4_4 src/UPDATING 1.73.2.43.2.50 src/contrib/sendmail/src/parseaddr.c 1.1.1.2.6.6.2.3 src/contrib/sendmail/src/version.c 1.1.1.3.2.7.2.2 src/sys/conf/newvers.sh 1.44.2.17.2.41 RELENG_4_3 src/UPDATING 1.73.2.28.2.37 src/contrib/sendmail/src/parseaddr.c 1.1.1.2.6.4.2.3 src/contrib/sendmail/src/version.c 1.1.1.3.2.4.2.2 src/sys/conf/newvers.sh 1.44.2.14.2.27 RELENG_3 src/contrib/sendmail/src/parseaddr.c 1.1.1.2.2.3 src/contrib/sendmail/src/version.c 1.1.1.2.2.3 - ------------------------------------------------------------------------- VII. References -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.3 (FreeBSD) iD8DBQE/aOHgFdaIBMps37IRAl09AKCVMKQCzC62EF7vZFnsZVoaGWpIMACfVGq0 0df1GogdqBVYUXzNBdHrwYA= =4xqj -----END PGP SIGNATURE-----