libssh2 Multiple Security Vulnerabilities



Date Discovered

March 18, 2019


libssh2 is prone to multiple security vulnerabilities. Attackers can exploit these issues to execute arbitrary code, perform unauthorized actions, cause denial-of-service conditions, retrieve sensitive information; other attacks may also be possible.

Technologies Affected

  • Fortinet Fortios 5.6.0
  • Fortinet Fortios 5.6.1
  • Fortinet Fortios 5.6.10
  • Fortinet Fortios 5.6.2
  • Fortinet Fortios 5.6.3
  • Fortinet Fortios 5.6.4
  • Fortinet Fortios 5.6.5
  • Fortinet Fortios 5.6.6
  • Fortinet Fortios 5.6.7
  • Fortinet Fortios 5.6.8
  • Fortinet Fortios 5.6.9
  • Fortinet Fortios 6.0.0
  • Fortinet Fortios 6.0.1
  • Fortinet Fortios 6.0.2
  • Fortinet Fortios 6.0.3
  • Fortinet Fortios 6.0.4
  • Fortinet Fortios 6.0.5
  • Fortinet Fortios 6.0.6
  • Fortinet Fortios 6.2.0
  • Oracle Linux 7
  • Oracle PeopleSoft Enterprise PeopleTools 8.56
  • Oracle PeopleSoft Enterprise PeopleTools 8.57
  • Redhat Enterprise Linux 6
  • Redhat Enterprise Linux 7
  • Redhat Virtualization 4
  • libssh2 libssh2 0.1
  • libssh2 libssh2 0.11
  • libssh2 libssh2 0.15
  • libssh2 libssh2 0.3
  • libssh2 libssh2 1.1
  • libssh2 libssh2 1.2.8
  • libssh2 libssh2 1.3.0
  • libssh2 libssh2 1.4.0
  • libssh2 libssh2 1.4.1
  • libssh2 libssh2 1.4.2
  • libssh2 libssh2 1.4.3
  • libssh2 libssh2 1.5.0
  • libssh2 libssh2 1.6.0
  • libssh2 libssh2 1.7.0
  • libssh2 libssh2 1.8.0


Run all software as a nonprivileged user with minimal access rights.
Ensure that all nonadministrative tasks, such as browsing the web and reading email, are performed as an unprivileged user with minimal access rights.

Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of anomalous or suspicious activity. This may indicate exploit attempts or activity that results from a successful exploit.

Do not follow links provided by unknown or untrusted sources.
To reduce the likelihood of successful exploits, never visit sites of questionable integrity or follow links provided by unfamiliar or untrusted sources.

Set web browser security to disable the execution of script code or active content.
To prevent a successful exploit of script-execution vulnerabilities, disable support for script code and active content within the client browser. Note that this tactic might adversely affect websites that rely on HTML or script code.

Implement multiple redundant layers of security.
Various memory-protection schemes (such as nonexecutable and randomly mapped memory segments) may hinder an attacker's ability to exploit memory corruption vulnerabilities.

Updates are available. Please see the references or vendor advisory for more information.



Chris Coulson of Canonical Ltd.

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