Date:         Tue, 22 Sep 2009 14:20:00 -0500
Reply-To:     Troy Dawson 
Sender:       Security Errata for Scientific Linux
              
From:         Troy Dawson 
Subject:      Security ERRATA Low: openssh on SL5.x i386/x86_64
Comments: To: "scientific-linux-errata@fnal.gov"
          

Synopsis:	Low: openssh security, bug fix, and enhancement update
Issue date:	2009-09-02
CVE Names:	CVE-2008-5161

CVE-2008-5161 OpenSSH: Plaintext Recovery Attack against CBC ciphers
A flaw was found in the SSH protocol. An attacker able to perform a
man-in-the-middle attack may be able to obtain a portion of plain text 
from an arbitrary ciphertext block when a CBC mode cipher was used to 
encrypt SSH communication. This update helps mitigate this attack: 
OpenSSH clients and servers now prefer CTR mode ciphers to CBC mode, and 
the OpenSSH server now reads SSH packets up to their full possible 
length when corruption is detected, rather than reporting errors early, 
reducing the possibility of successful plain text recovery. (CVE-2008-5161)

This update also fixes the following bug:

* the ssh client hung when trying to close a session in which a 
background process still held tty file descriptors open. With this 
update, this so-called "hang on exit" error no longer occurs and the ssh 
client closes the session immediately. (BZ#454812)

In addition, this update adds the following enhancements:

* the SFTP server can now chroot users to various directories, including
a user's home directory, after log in. A new configuration option --
ChrootDirectory -- has been added to "/etc/ssh/sshd_config" for setting
this up (the default is not to chroot users). Details regarding 
configuring this new option are in the sshd_config(5) manual page. 
(BZ#440240)

* the executables which are part of the OpenSSH FIPS module which is 
being validated will check their integrity and report their FIPS mode 
status to the system log or to the terminal. (BZ#467268, BZ#492363)

After installing this update, the OpenSSH server daemon (sshd) will be 
restarted automatically.

Note: fipscheck update needed for dependencies.

SL 5.x

     SRPMS:
openssh-4.3p2-36.el5.src.rpm
fipscheck-1.2.0-1.el5.src.rpm
     i386:
fipscheck-1.2.0-1.el5.i386.rpm
fipscheck-devel-1.2.0-1.el5.i386.rpm
fipscheck-lib-1.2.0-1.el5.i386.rpm
openssh-4.3p2-36.el5.i386.rpm
openssh-askpass-4.3p2-36.el5.i386.rpm
openssh-clients-4.3p2-36.el5.i386.rpm
openssh-server-4.3p2-36.el5.i386.rpm
     x86_64:
fipscheck-1.2.0-1.el5.i386.rpm
fipscheck-devel-1.2.0-1.el5.i386.rpm
fipscheck-lib-1.2.0-1.el5.i386.rpm
openssh-4.3p2-36.el5.i386.rpm
openssh-askpass-4.3p2-36.el5.i386.rpm
openssh-clients-4.3p2-36.el5.i386.rpm
openssh-server-4.3p2-36.el5.i386.rpm

-Connie Sieh
-Troy Dawson

SciLinux: CVE-2008-5161 Low: openssh SL5.x i386/x86_64

Low: openssh security, bug fix, and enhancement update

Summary

Date:         Tue, 22 Sep 2009 14:20:00 -0500Reply-To:     Troy Dawson Sender:       Security Errata for Scientific Linux              From:         Troy Dawson Subject:      Security ERRATA Low: openssh on SL5.x i386/x86_64Comments: To: "scientific-linux-errata@fnal.gov"          Synopsis:	Low: openssh security, bug fix, and enhancement updateIssue date:	2009-09-02CVE Names:	CVE-2008-5161CVE-2008-5161 OpenSSH: Plaintext Recovery Attack against CBC ciphersA flaw was found in the SSH protocol. An attacker able to perform aman-in-the-middle attack may be able to obtain a portion of plain text from an arbitrary ciphertext block when a CBC mode cipher was used to encrypt SSH communication. This update helps mitigate this attack: OpenSSH clients and servers now prefer CTR mode ciphers to CBC mode, and the OpenSSH server now reads SSH packets up to their full possible length when corruption is detected, rather than reporting errors early, reducing the possibility of successful plain text recovery. (CVE-2008-5161)This update also fixes the following bug:* the ssh client hung when trying to close a session in which a background process still held tty file descriptors open. With this update, this so-called "hang on exit" error no longer occurs and the ssh client closes the session immediately. (BZ#454812)In addition, this update adds the following enhancements:* the SFTP server can now chroot users to various directories, includinga user's home directory, after log in. A new configuration option --ChrootDirectory -- has been added to "/etc/ssh/sshd_config" for settingthis up (the default is not to chroot users). Details regarding configuring this new option are in the sshd_config(5) manual page. (BZ#440240)* the executables which are part of the OpenSSH FIPS module which is being validated will check their integrity and report their FIPS mode status to the system log or to the terminal. (BZ#467268, BZ#492363)After installing this update, the OpenSSH server daemon (sshd) will be restarted automatically.Note: fipscheck update needed for dependencies.SL 5.x     SRPMS:openssh-4.3p2-36.el5.src.rpmfipscheck-1.2.0-1.el5.src.rpm     i386:fipscheck-1.2.0-1.el5.i386.rpmfipscheck-devel-1.2.0-1.el5.i386.rpmfipscheck-lib-1.2.0-1.el5.i386.rpmopenssh-4.3p2-36.el5.i386.rpmopenssh-askpass-4.3p2-36.el5.i386.rpmopenssh-clients-4.3p2-36.el5.i386.rpmopenssh-server-4.3p2-36.el5.i386.rpm     x86_64:fipscheck-1.2.0-1.el5.i386.rpmfipscheck-devel-1.2.0-1.el5.i386.rpmfipscheck-lib-1.2.0-1.el5.i386.rpmopenssh-4.3p2-36.el5.i386.rpmopenssh-askpass-4.3p2-36.el5.i386.rpmopenssh-clients-4.3p2-36.el5.i386.rpmopenssh-server-4.3p2-36.el5.i386.rpm-Connie Sieh-Troy Dawson



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