Completing the Implementation of SSH Library Modernization 

Change

In mid-2017, ssh_get_info2.nasl was introduced, leveraging the sshlib library effort that streamlined new ssh connectivity for scan targets. The original SSH/RSH/RLOGIN connectivity plugin 12643 and associated ssh library had 13+ years of legacy connectivity plugins built on top of them. These legacy ssh library dependent plugins have been steadily migrated to the new ssh_get_info2 library as updates to the plugins have been needed. Over the past 12 months, there has been a push to port the few remaining plugins that rely on the legacy ssh_get_info library to the new ssh_get_info2 library and this effort will soon be complete.

The current SSH detection plugin, ssh_get_info2 (97993), currently falls back to the legacy detection plugin, ssh_get_info.nasl (12634), if it encounters an error. After this change, that fall back will no longer happen. All plugin transitions from the legacy ssh_get_info to the new ssh_get_info2 calls have been thoroughly tested and closely watched via telemetry to ensure functionality has not been negatively impacted.

Impact

Ideally, there will be no noticeable impact from these changes.  However, from time to time against certain targets the legacy library has been able to succeed in running commands and gathering results when the current library fails. Going forward, the failure of the current SSH library will appear as an error and plugins may fail to report when formerly they would succeed. 

Affected Plugins

This change will happen for every Nessus plugin that runs SSH commands against a remote target.  Compliance audits, Nessus agent scans and Tenable scans that use a sensor other than Nessus will not be impacted. 

Target Release Date

November 27, 2023

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