Security Advisory 2021-08
| Summary | Remote Code Execution via Deserialisation in the Halibut Protocol (CVE-2021-31819) |
| Advisory Number | 2021-08 |
| Discovery Date | 21 Jul 2021 |
| Patch Release Date | 31 Aug 2021 |
| Advisory Release Date | 22 Sep 2021 |
| Product | Halibut |
| Operating System | N/A |
| Severity | High |
| CVE ID | CVE-2021-31819 |
Customers who have upgraded Halibut to version 4.4.7 or higher are not affected.
Severity
Octopus Deploy has given this vulnerability a high rating. This rating was given according to the Octopus Deploy severity 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.
Details
In Halibut versions prior to 4.4.7 there is a deserialisation vulnerability that could allow remote code execution on systems that already trust each other based on certificate verification.
The versions of Halibut affected by this vulnerability are:
- All versions of Halibut before version 4.4.7.
Fix
To address this vulnerability, we have released Halibut version:
- 4.4.7 which contains a fix for this issue.
If you are using Halibut in your projects please update Halibut to the latest version which can downloaded from https://www.nuget.org/packages/Halibut/
What You Need to Do
Octopus Deploy recommends that you upgrade to the latest version (4.4.7). You can download the latest version of Halibut from https://www.nuget.org/packages/Halibut/
Mitigation
There is no known mitigation for CVE-2021-31819, it is important to upgrade to a fixed version as soon as possible.
Support
If you have any questions or concerns regarding this advisory, please contact our support team https://octopus.com/support.
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.
Source
This vulnerability was discovered by Ashley Donaldson from Beyond Binary.