Security update for openssh

SUSE Security Update: Security update for openssh
Announcement ID: SUSE-SU-2018:3776-1
Rating: moderate
References: #1091396 #1105010 #1106163 #964336 #982273
Cross-References:CVE-2018-15473 CVE-2018-15919
Affected Products:
  • SUSE Linux Enterprise Server 12-SP1-LTSS
  • SUSE Linux Enterprise Server 12-LTSS

An update that solves two vulnerabilities and has three fixes is now available.

Description:

This update for openssh fixes the following issues:
Following security issues have been fixed:

  • CVE-2018-15919: Remotely observable behaviour in auth-gss2.c in OpenSSH could be used by remote attackers to detect existence of users on a target system when GSS2 is in use. OpenSSH developers do not want to treat such a username enumeration (or "oracle") as a vulnerability. (bsc#1106163)
  • CVE-2018-15473: OpenSSH was prone to a user existance oracle vulnerability due to not delaying bailout for an invalid authenticating user until after the packet containing the request has been fully parsed, related to auth2-gss.c, auth2-hostbased.c, and auth2-pubkey.c. (bsc#1105010)

Also the following security related hardening change was done:
  • Remove arcfour,cast,blowfish from list of default ciphers. (bsc#982273)

And the following non-security issues were fixed:
  • Stop leaking File descriptors (bsc#964336)
  • sftp-client.c returns wrong error code upon failure (bsc#1091396)

Patch Instructions:

To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Alternatively you can run the command listed for your product:

  • SUSE Linux Enterprise Server 12-SP1-LTSS:
    zypper in -t patch SUSE-SLE-SERVER-12-SP1-2018-2698=1
  • SUSE Linux Enterprise Server 12-LTSS:
    zypper in -t patch SUSE-SLE-SERVER-12-2018-2698=1

Package List:

  • SUSE Linux Enterprise Server 12-SP1-LTSS (ppc64le s390x x86_64):
    • openssh-6.6p1-54.18.1
    • openssh-askpass-gnome-6.6p1-54.18.1
    • openssh-askpass-gnome-debuginfo-6.6p1-54.18.1
    • openssh-debuginfo-6.6p1-54.18.1
    • openssh-debugsource-6.6p1-54.18.1
    • openssh-fips-6.6p1-54.18.1
    • openssh-helpers-6.6p1-54.18.1
    • openssh-helpers-debuginfo-6.6p1-54.18.1
  • SUSE Linux Enterprise Server 12-LTSS (ppc64le s390x x86_64):
    • openssh-6.6p1-54.18.1
    • openssh-askpass-gnome-6.6p1-54.18.1
    • openssh-askpass-gnome-debuginfo-6.6p1-54.18.1
    • openssh-debuginfo-6.6p1-54.18.1
    • openssh-debugsource-6.6p1-54.18.1
    • openssh-fips-6.6p1-54.18.1
    • openssh-helpers-6.6p1-54.18.1
    • openssh-helpers-debuginfo-6.6p1-54.18.1

References: