The Bastion SSH Session Recording Ttyrec Files Not Signed After Encryption Vulnerability

A vulnerability exists in The Bastion's SSH session recording feature, specifically in versions prior to 3.22.00. The issue arises in the 'osh-encrypt-rsync' script, which is designed to rotate, encrypt, sign, and copy 'ttyrec' files to remote storage. While the script correctly encrypts the files using the specified GPG keys, it fails to sign them as intended. This oversight creates a risk of unauthorized tampering with the 'ttyrec' files, as the absence of a GPG signature makes it difficult to detect modifications.

Impact

The lack of a GPG signature on the encrypted 'ttyrec' files, despite the script being configured to sign them, undermines the expected verification and non-repudiation assurances. This flaw could allow an individual with high privileges to alter the 'ttyrec' files without detection, especially if they have access to the public GPG keys used for encryption.

Remediation

Users can update to The Bastion version 3.22.00 or later, where this vulnerability has been addressed.