From cfb6d9c7fdb3507e5bf5c6d9790601c445502fae Mon Sep 17 00:00:00 2001 From: Adolf Belka Date: Tue, 26 Dec 2023 14:10:34 +0100 Subject: [PATCH] postfix: Update to version 3.8.4 + prevent smtp smuggling MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit - Update from version 3.8.3 to 3.8.4 - Update of rootfile not required - Permanent fix for smtp smuggling will be in version 3.9. However the fix has been backported into version 3.8.4 but with the default for the parameter of "no". - This patch sets the defaults for all the main.cf parameters highlighted by Wietse Venema in http://www.postfix.org/smtp-smuggling.html - Additionally the implementation of smtpd_forbid_bare_newline = yes has been added to the install.sh pak for postfix so that it will be included into any main.cf file being restored from backup. This parameter is available for the first time in 3.8.4 so will not be in any backup prior to this release and can therefore be safely applied to restored versions of main.cf. - This fix in install.sh will be able to be removed when version 3.9 is released early in 2024 as the default for that parameter in that version onwards will then be "yes" - Changelog 3.8.4 Security: with "smtpd_forbid_bare_newline = yes" (default "no" for Postfix < 3.9), reply with "Error: bare received" and disconnect when an SMTP client sends a line ending in , violating the RFC 5321 requirement that lines must end in . This prevents SMTP smuggling attacks that target a recipient at a Postfix server. For backwards compatibility, local clients are excluded by default with "smtpd_forbid_bare_newline_exclusions = $mynetworks". Files: mantools/postlink, proto/postconf.proto, global/mail_params.h, global/smtp_stream.c, global/smtp_stream.h, smtpd/smtpd.c. Signed-off-by: Adolf Belka Reviewed-by: Peter Müller --- lfs/postfix | 15 +++++++++++---- src/paks/postfix/install.sh | 5 +++++ 2 files changed, 16 insertions(+), 4 deletions(-) diff --git a/lfs/postfix b/lfs/postfix index aab683f4c3..7f2625a4e8 100644 --- a/lfs/postfix +++ b/lfs/postfix @@ -26,7 +26,7 @@ include Config SUMMARY = A fast, secure, and flexible mailer -VER = 3.8.3 +VER = 3.8.4 THISAPP = postfix-$(VER) DL_FILE = $(THISAPP).tar.gz @@ -34,7 +34,7 @@ DL_FROM = $(URL_IPFIRE) DIR_APP = $(DIR_SRC)/$(THISAPP) TARGET = $(DIR_INFO)/$(THISAPP) PROG = postfix -PAK_VER = 43 +PAK_VER = 44 DEPS = @@ -70,7 +70,7 @@ objects = $(DL_FILE) $(DL_FILE) = $(DL_FROM)/$(DL_FILE) -$(DL_FILE)_BLAKE2 = a656606c2a46671548cb954a65d769ba5bf68a5c8f0ccdc0e753b03386956eef3e264b696a306c586f1df1b06fb173e5f3db74c6a9e4d3686c86b8f53be585ed +$(DL_FILE)_BLAKE2 = 200ce3d72444da05e42fc8627002d53d68c1b3d78b7f74b0130ac958c23d16454783ef4849a8c9a4e3cba8ae36646e921f7e94ac4fb819b597e1a5ab1a875272 install : $(TARGET) @@ -110,13 +110,20 @@ $(TARGET) : $(patsubst %,$(DIR_DL)/%,$(objects)) cd $(DIR_APP) && sh postfix-install -non-interactive ## Install configuration rm -vf /etc/postfix/main.cf.default + + # update main.cf parameters to prevent smtp smuggling attack + postconf -e 'smtpd_forbid_bare_newline = yes' + postconf -e 'smtpd_forbid_unauth_pipelining = yes' + postconf -e 'smtpd_data_restrictions = reject_unauth_pipelining' + postconf -e 'smtpd_discard_ehlo_keywords = chunking' + mkdir -p /var/lib/postfix chown postfix.root /var/lib/postfix install -v -m 644 $(DIR_SRC)/config/backup/includes/postfix \ /var/ipfire/backup/addons/includes/postfix mv /usr/sbin/sendmail /usr/sbin/sendmail.postfix - + #install initscripts $(call INSTALL_INITSCRIPTS,$(SERVICES)) diff --git a/src/paks/postfix/install.sh b/src/paks/postfix/install.sh index 1629d21c18..2e04e74a86 100644 --- a/src/paks/postfix/install.sh +++ b/src/paks/postfix/install.sh @@ -24,6 +24,11 @@ . /opt/pakfire/lib/functions.sh extract_files restore_backup ${NAME} + +# change main.cf parameter from default value to prevent smtp smuggling attack +# will not be required once postfix-3.9.x is released as default will then be yes +postconf -e 'smtpd_forbid_bare_newline = yes' + postalias /etc/aliases # Set postfix's hostname postconf -e "myhostname=$(hostname -f)" -- 2.39.5