Nessus versions 8.11.0 and earlier were found to maintain sessions longer than the permitted period in certain scenarios. The lack of proper session expiration could allow attackers with local access to login into an existing browser session.

Nessus 8.10.0 and earlier were found to contain a Stored XSS vulnerability due to improper validation of input during scan configuration. An authenticated, remote attacker could potentially exploit this vulnerability to execute arbitrary code in a user's session. Tenable has implemented additional input validation mechanisms to correct this issue in Nessus 8.11.0.

Nessus versions 8.6.0 and earlier were found to contain a Denial of Service vulnerability due to improper validation of specific imported scan types. An authenticated, remote attacker could potentially exploit this vulnerability to cause a Nessus scanner to become temporarily unresponsive.

Nessus 8.5.2 and earlier on Windows platforms were found to contain an issue where certain system files could be overwritten arbitrarily, potentially creating a denial of service condition.

Content Injection vulnerability in Tenable Nessus prior to 8.5.0 may allow an authenticated, local attacker to exploit this vulnerability by convincing another targeted Nessus user to view a malicious URL and use Nessus to send fraudulent messages. Successful exploitation could allow the authenticated adversary to inject arbitrary text into the feed status, which will remain saved post session expiration.

Nessus versions 8.4.0 and earlier were found to contain a reflected XSS vulnerability due to improper validation of user-supplied input. An unauthenticated, remote attacker could potentially exploit this vulnerability via a specially crafted request to execute arbitrary script code in a users browser session.