Insufficiently Protected Credentials: An authenticated user with debug privileges can retrieve stored Nessus policy credentials from the “nessusd” process in cleartext via process dumping. The affected products are all versions of Nessus Essentials and Professional. The vulnerability allows an attacker to access credentials stored in Nessus scanners, potentially compromising its customers’ network of assets.

An authenticated attacker could read Nessus Debug Log file attachments from the web UI without having the correct privileges to do so. This may lead to the disclosure of information on the scan target and/or the Nessus scan to unauthorized parties able to reach the Nessus instance.

An authenticated attacker could utilize the identical agent and cluster node linking keys to potentially allow for a scenario where unauthorized disclosure of agent logs and data is present.

In Nessus versions prior to 10.8.4, a non-authenticated attacker could alter Nessus logging entries by manipulating http requests to the application.

A privilege escalation vulnerability was identified in Nessus versions 8.10.1 through 8.15.8 and 10.0.0 through 10.4.1. An authenticated attacker could potentially execute a specially crafted file to obtain root or NT AUTHORITY / SYSTEM privileges on the Nessus host.

As part of our Security Development Lifecycle, a potential privilege escalation issue was identified internally. This could allow a malicious actor with sufficient permissions to modify environment variables and abuse an impacted plugin in order to escalate privileges. We have resolved the issue and also made several defense-in-depth fixes alongside. While the probability of successful exploitation is low, Tenable is committed to securing our customers’ environments and our products. The updates have been distributed via the Tenable plugin feed in feed serial numbers equal to or greater than #202212212055.

A vulnerability was reported where through modifying the scan variables, an authenticated user in Tenable products, that has Scan Policy Configuration roles, could manipulate audit policy variables to execute arbitrary commands on credentialed scan targets.

An arbitrary file write vulnerability exists where an authenticated, remote attacker with administrator privileges on the Nessus application could alter Nessus Rules variables to overwrite arbitrary files on the remote host, which could lead to a denial of service condition.

Under certain conditions, a low privileged attacker could load a specially crafted file during installation or upgrade to escalate privileges on Windows and Linux hosts.

Nessus versions 8.2.1 and earlier were found to contain a stored XSS vulnerability due to improper validation of user-supplied input. An authenticated, remote attacker could potentially exploit this vulnerability via a specially crafted request to execute arbitrary script code in a user's browser session. Tenable has released Nessus 8.2.2 to address this issue.

An improper authorization vulnerability exists where an authenticated, low privileged remote attacker could view a list of all the users available in the application.

An arbitrary file write vulnerability exists where an authenticated, remote attacker with administrator privileges could alter logging variables to overwrite arbitrary files on the remote host with log data, which could lead to a denial of service condition.

A pass-back vulnerability exists where an authenticated, remote attacker with administrator privileges could uncover stored SMTP credentials within the Nessus application.This issue affects Nessus: before 10.6.0.

In Nessus before 7.1.0, Session Fixation exists due to insufficient session management within the application. An authenticated attacker could maintain system access due to session fixation after a user password change.

When linking a Nessus scanner or agent to Tenable.io or other manager, Nessus 6.x before 6.11 does not verify the manager's TLS certificate when making the initial outgoing connection. This could allow man-in-the-middle attacks.

When installing Nessus to a directory outside of the default location, Nessus versions prior to 7.0.3 did not enforce secure permissions for sub-directories. This could allow for local privilege escalation if users had not secured the directories in the installation location.

Tenable Nessus before 6.8 has a stored XSS issue that requires admin-level authentication to the Nessus UI, and would potentially impact other admins (Tenable IDs 5218 and 5269).

Tenable Nessus before 6.8 has a stored XSS issue that requires admin-level authentication to the Nessus UI, and would only potentially impact other admins. (Tenable ID 5198).

Cross-site scripting vulnerability in Nessus versions 6.8.0, 6.8.1, 6.9.0, 6.9.1 and 6.9.2 allows remote authenticated attackers to inject arbitrary web script or HTML via unspecified vectors.

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.

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 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.

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 8.15.2 and earlier were found to contain a local privilege escalation vulnerability which could allow an authenticated, local administrator to run specific executables on the Nessus Agent host. Tenable has included a fix for this issue in Nessus 10.0.0. The installation files can be obtained from the Tenable Downloads Portal (https://www.tenable.com/downloads/nessus).

Nessus Agent 8.2.4 and earlier for Windows were found to contain multiple local privilege escalation vulnerabilities which could allow an authenticated, local administrator to run specific Windows executables as the Nessus host. This is different than CVE-2021-20099.

Nessus Agent versions 8.2.5 and earlier were found to contain a privilege escalation vulnerability which could allow a Nessus administrator user to upload a specially crafted file that could lead to gaining administrator privileges on the Nessus host.

Nessus versions 8.13.2 and earlier were found to contain a privilege escalation vulnerability which could allow a Nessus administrator user to upload a specially crafted file that could lead to gaining administrator privileges on the Nessus host.

Nessus Agent 8.2.4 and earlier for Windows were found to contain multiple local privilege escalation vulnerabilities which could allow an authenticated, local administrator to run specific Windows executables as the Nessus host. This is different than CVE-2021-20100.

An authenticated attacker could create an audit file that bypasses PowerShell cmdlet checks and executes commands with administrator privileges.

An authenticated attacker could read arbitrary files from the underlying operating system of the scanner using a custom crafted compliance audit file without providing any valid SSH credentials.