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Red Hat: RHSA-2016-0428-01 Moderate: libssh2 Type Confusion Security Update

red hat
Calendar Grey March 10, 2016
Scroller Redhat
Severity classified as Moderate: Revised libssh2 software package addressing SSH vulnerability in Red Hat Enterprise Linux systems.
Updated libssh2 packages that fix one security issue are now available for Red Hat Enterprise Linux 6 and 7

Solution

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

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Summary

The libssh2 packages provide a library that implements the SSHv2 protocol.
A type confusion issue was found in the way libssh2 generated ephemeral secrets for the diffie-hellman-group1 and diffie-hellman-group14 key exchange methods. This would cause an SSHv2 Diffie-Hellman handshake to use significantly less secure random parameters. (CVE-2016-0787)
Red Hat would like to thank Aris Adamantiadis for reporting this issue.
All libssh2 users are advised to upgrade to these updated packages, which contain a backported patch to correct this issue. After installing these updated packages, all running applications using libssh2 must be restarted for this update to take effect.

Topics%20covered

Topics Covered

security advisory Red Hat moderate threat security impact libssh2 type confusion SSH update

References

https://access.redhat.com/security/cve/CVE-2016-0787 https://access.redhat.com/security/updates/classification#moderate

Package List

Red Hat Enterprise Linux Desktop (v. 6):
Source: libssh2-1.4.2-2.el6_7.1.src.rpm
i386: libssh2-1.4.2-2.el6_7.1.i686.rpm libssh2-debuginfo-1.4.2-2.el6_7.1.i686.rpm
x86_64: libssh2-1.4.2-2.el6_7.1.i686.rpm libssh2-1.4.2-2.el6_7.1.x86_64.rpm libssh2-debuginfo-1.4.2-2.el6_7.1.i686.rpm libssh2-debuginfo-1.4.2-2.el6_7.1.x86_64.rpm
Red Hat Enterprise Linux Desktop Optional (v. 6):
i386: libssh2-debuginfo-1.4.2-2.el6_7.1.i686.rpm libssh2-devel-1.4.2-2.el6_7.1.i686.rpm libssh2-docs-1.4.2-2.el6_7.1.i686.rpm
x86_64: libssh2-debuginfo-1.4.2-2.el6_7.1.i686.rpm libssh2-debuginfo-1.4.2-2.el6_7.1.x86_64.rpm libssh2-devel-1.4.2-2.el6_7.1.i686.rpm libssh2-devel-1.4.2-2.el6_7.1.x86_64.rpm libssh2-docs-1.4.2-2.el6_7.1.x86_64.rpm
Red Hat Enterprise Linux HPC Node (v. 6):
Source: libssh2-1.4.2-2.el6_7.1.src.rpm
x86_64: libssh2-1.4.2-2.el6_7.1.i686.rpm libssh2-1.4.2-2.el6_7.1.x86_64.rpm libssh2-debuginfo-1.4.2-2.el6_7.1.i686.rpm libssh2-debuginfo-1.4.2-2.el6_7.1.x86_64.rpm
Red Hat Enterprise Linux HPC Node Optional (v. 6):
x86_64: libssh2-debuginfo-1.4.2-2.el6_7.1.i686.rpm libssh2-debuginfo-1.4.2-2.el6_7.1.x86_64.rpm libssh2-devel-1.4.2-2.el6_7.1.i686.rpm libssh2-devel-1.4.2-2.el6_7.1.x86_64.rpm libssh2-docs-1.4.2-2.el6_7.1.x86_64.rpm
Red Hat Enterprise Linux Server (v. 6):
Source:

Read the Full Advisory


Advisory ID: RHSA-2016:0428-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2016:0428.html
Issue date: 2016-03-10

Topic

Updated libssh2 packages that fix one security issue are now available for Red Hat Enterprise Linux 6 and 7.Red Hat Product Security has rated this update as having Moderate securityimpact. A Common Vulnerability Scoring System (CVSS) base score, whichgives a detailed severity rating, is available from the CVE link in theReferences section.

Topics%20covered

Topics Covered

security advisory Red Hat moderate threat security impact libssh2 type confusion SSH update

Relevant Releases Architectures

Red Hat Enterprise Linux Client (v. 7) - x86_64

Red Hat Enterprise Linux Client Optional (v. 7) - noarch, x86_64

Red Hat Enterprise Linux ComputeNode (v. 7) - x86_64

Red Hat Enterprise Linux ComputeNode Optional (v. 7) - noarch, x86_64

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 (v. 7) - ppc64, ppc64le, s390x, x86_64

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

Red Hat Enterprise Linux Server Optional (v. 7) - noarch, ppc64, ppc64le, s390x, x86_64

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

Red Hat Enterprise Linux Workstation (v. 7) - x86_64

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

Red Hat Enterprise Linux Workstation Optional (v. 7) - noarch, x86_64

Bugs Fixed

1306021 - CVE-2016-0787 libssh2: bits/bytes confusion resulting in truncated Diffie-Hellman secret length

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