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Alerts This Week
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Alerts This Week
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Moderate Risk of Postfix TLS Injection in Red Hat Enterprise Linux 6

red hat
Calendar Grey April 6, 2011
Scroller Redhat
Red Hat issues a significant security alert for postfix to mitigate a TLS vulnerability in Enterprise Linux 6.
Updated postfix packages that fix one security issue are now available for Red Hat Enterprise Linux 6

Solution

Before applying this update, make sure all previously-released errata relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259

Summary

Postfix is a Mail Transport Agent (MTA), supporting LDAP, SMTP AUTH (SASL), and TLS.
It was discovered that Postfix did not flush the received SMTP commands buffer after switching to TLS encryption for an SMTP session. A man-in-the-middle attacker could use this flaw to inject SMTP commands into a victim's session during the plain text phase. This would lead to those commands being processed by Postfix after TLS encryption is enabled, possibly allowing the attacker to steal the victim's mail or authentication credentials. (CVE-2011-0411)
Red Hat would like to thank the CERT/CC for reporting CVE-2011-0411. The CERT/CC acknowledges Wietse Venema as the original reporter.
Users of Postfix are advised to upgrade to these updated packages, which contain a backported patch to resolve this issue. After installing this update, the postfix service will be restarted automatically.

Topics%20covered

Topics Covered

security advisory security update Red Hat Enterprise Linux postfix moderate security mail transport agent TLS injection

References

https://access.redhat.com/security/cve/CVE-2011-0411 https://access.redhat.com/security/updates/classification/#moderate

Package List

Red Hat Enterprise Linux Desktop (v. 6):
Source:
i386: postfix-2.6.6-2.1.el6_0.i686.rpm postfix-debuginfo-2.6.6-2.1.el6_0.i686.rpm
x86_64: postfix-2.6.6-2.1.el6_0.x86_64.rpm postfix-debuginfo-2.6.6-2.1.el6_0.x86_64.rpm
Red Hat Enterprise Linux Desktop Optional (v. 6):
Source:
i386: postfix-debuginfo-2.6.6-2.1.el6_0.i686.rpm postfix-perl-scripts-2.6.6-2.1.el6_0.i686.rpm
x86_64: postfix-debuginfo-2.6.6-2.1.el6_0.x86_64.rpm postfix-perl-scripts-2.6.6-2.1.el6_0.x86_64.rpm
Red Hat Enterprise Linux HPC Node (v. 6):
Source:
x86_64: postfix-2.6.6-2.1.el6_0.x86_64.rpm postfix-debuginfo-2.6.6-2.1.el6_0.x86_64.rpm
Red Hat Enterprise Linux HPC Node Optional (v. 6):
Source:
x86_64: postfix-debuginfo-2.6.6-2.1.el6_0.x86_64.rpm postfix-perl-scripts-2.6.6-2.1.el6_0.x86_64.rpm
Red Hat Enterprise Linux Server (v. 6):
Source:
i386: postfix-2.6.6-2.1.el6_0.i686.rpm postfix-debuginfo-2.6.6-2.1.el6_0.i686.rpm
ppc64: postfix-2.6.6-2.1.el6_0.ppc64.rpm postfix-debuginfo-2.6.6-2.1.el6_0.ppc64.rpm
s390x: postfix-2.6.6-2.1.el6_0.s390x.rpm postfix-debuginfo-2.6.6-2.1.el6_0.s390x.rpm
x86_64: postfix-2.6.6-2.1.el6_0.x86_64.rpm postfix-debuginfo-2.6.6-2.1.el6_0.x86_64.rpm
Red Hat Enterprise Linux Server Optional (v. 6):
Source:
i386: postfix-debuginfo-2.6.6-2.1.el6_0.i686.rpm

Read the Full Advisory


Advisory ID: RHSA-2011:0423-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2011:0423.html
Issue date: 2011-04-06

Topic

Updated postfix packages that fix one security issue are now available forRed Hat Enterprise Linux 6.The Red Hat Security Response Team has rated this update as having moderatesecurity impact. A Common Vulnerability Scoring System (CVSS) base score,which gives a detailed severity rating, is available from the CVE link inthe References section.

Topics%20covered

Topics Covered

security advisory security update Red Hat Enterprise Linux postfix moderate security mail transport agent TLS injection

Relevant Releases Architectures

Red Hat Enterprise Linux Desktop (v. 6) - i386, x86_64

Red Hat Enterprise Linux Desktop Optional (v. 6) - i386, x86_64

Red Hat Enterprise Linux HPC Node (v. 6) - x86_64

Red Hat Enterprise Linux HPC Node Optional (v. 6) - x86_64

Red Hat Enterprise Linux Server (v. 6) - i386, ppc64, s390x, x86_64

Red Hat Enterprise Linux Server Optional (v. 6) - i386, ppc64, s390x, x86_64

Red Hat Enterprise Linux Workstation (v. 6) - i386, x86_64

Red Hat Enterprise Linux Workstation Optional (v. 6) - i386, x86_64

Bugs Fixed

674814 - CVE-2011-0411 postfix: SMTP commands injection during plaintext to TLS session switch

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