A libssh: Denial of Service security update is available for Gentoo Linux.
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Gentoo Linux Security Advisory GLSA 202004-08
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https://security.gentoo.org/
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Severity: Low
Title: libssh: Denial of Service
Date: April 10, 2020
Bugs: #716788
ID: 202004-08
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Synopsis
========
A vulnerability in libssh could allow a remote attacker to cause a
Denial of Service condition.
Background
==========
libssh is a multiplatform C library implementing the SSHv2 protocol on
client and server side.
Affected packages
=================
-------------------------------------------------------------------
Package / Vulnerable / Unaffected
-------------------------------------------------------------------
1 net-libs/libssh < 0.9.4 >= 0.9.4
Description
===========
It was discovered that libssh could crash when AES-CTR ciphers are
used.
Impact
======
A remote attacker running a malicious client or server could possibly
crash the counterpart implemented with libssh and cause a Denial of
Service condition.
Workaround
==========
Disable AES-CTR ciphers. If you implement a server using libssh it is
recommended to use a prefork model so each session runs in an own
process.
Resolution
==========
All libssh users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=net-libs/libssh-0.9.4"
References
==========
[ 1 ] CVE-2020-1730
https://nvd.nist.gov/vuln/detail/CVE-2020-1730
Availability
============
This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:
https://security.gentoo.org/glsa/202004-08
Concerns?
=========
Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users' machines is of utmost
importance to us. Any security concerns should be addressed to
security@gentoo.org or alternatively, you may file a bug at
https://bugs.gentoo.org.
License
=======
Copyright 2020 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).
The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.
https://creativecommons.org/licenses/by-sa/2.5
