2021-11 - Local privilege escalation in Octopus Tentacle (CVE-2021-31822)

Advisory Number


Discovery Date

Patch Release Date

Advisory Release Date


Octopus Tentacle

Operating System







Customers who have upgraded Octopus Tentacle to version 6.1.1116 or higher are not affected.


Octopus Deploy has given this vulnerability a High rating. This rating was given according to the Octopus Deploy security levels, which ranks vulnerabilities as critical, high, medium, or low severity.

This is our assessment and you should evaluate its applicability to your own environment.


When Octopus Tentacle is installed on a Linux operating system, the systemd service file permissions are misconfigured. This could lead to a local unprivileged user modifying the contents of the systemd service file to gain privileged access.

All versions of Octopus Tentacle are affected by this vulnerability.


To address this vulnerability, we have released Octopus Tentacle version:

  • 6.1.1116

The latest versions of Octopus Deploy products can be downloaded from and previous versions can be downloaded from

What You Need to Do

Octopus Deploy recommends that you upgrade to the latest version and reconfigure the Octopus Tentacle (6.1.1116). If you are unable to reconfigure the Tentacle then please implement the mitigation. You can download the latest version of Octopus Tentacle from

If you can’t upgrade to the latest version (6.1.1116):

If you have feature version…

…then upgrade to this version

3.X or greater


For Octopus Tentacle versions before 3.x please contact our support team ( ) for advice on upgrading to the latest version.


The file permissions for the systemd unit file can be manually updated to “644" by using the "chmod" command. The installation location for the Tentacle systemd unit file is /etc/systemd/system/<Name of Tentacle instance (default Tentacle)>.service.

For the default Tentance instance name the mitigation is:

chmod 644 /etc/systemd/system/Tentacle.service


If you have any questions or concerns regarding this advisory, please contact our support team (

Exploitation and Public Announcements

The Octopus Deploy security team is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.


This vulnerability was found by an Octopus Deploy customer.

Revision History

Version Date Comment
Current Version (v. 3) Nov 19, 2021 01:20 @a user
v. 2 Nov 11, 2021 03:47 @a user
v. 1 Nov 10, 2021 01:29 @a user