RHSA-2019:2136 - Security Advisory

Topic

An update for libssh2 is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

The libssh2 packages provide a library that implements the SSH2 protocol.

The following packages have been upgraded to a later upstream version: libssh2 (1.8.0). (BZ#1592784)

Security Fix(es):

• libssh2: Zero-byte allocation with a specially crafted SFTP packed leading to an out-of-bounds read (CVE-2019-3858)
• libssh2: Out-of-bounds reads with specially crafted SSH packets (CVE-2019-3861)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Red Hat Enterprise Linux 7.7 Release Notes linked from the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

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

After installing these updated packages, all running applications using libssh2 must be restarted for this update to take effect.

Affected Products

• Red Hat Enterprise Linux Server 7 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 7 x86_64
• Red Hat Enterprise Linux Workstation 7 x86_64
• Red Hat Enterprise Linux Desktop 7 x86_64
• Red Hat Enterprise Linux for IBM z Systems 7 s390x
• Red Hat Enterprise Linux for Power, big endian 7 ppc64
• Red Hat Enterprise Linux for Scientific Computing 7 x86_64
• Red Hat Enterprise Linux for Power, little endian 7 ppc64le
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7 s390x
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7 ppc64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7 ppc64le

Fixes

• BZ - 1687306 - CVE-2019-3858 libssh2: Zero-byte allocation with a specially crafted SFTP packed leading to an out-of-bounds read
• BZ - 1687311 - CVE-2019-3861 libssh2: Out-of-bounds reads with specially crafted SSH packets

CVEs

• CVE-2019-3858
• CVE-2019-3861

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/7.7_release_notes/index