CVE-2023-36736: Microsoft Identity Linux Broker Remote Code Execution Vulnerability

Overview

Severity
Medium (CVSS 4.4)
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C
Category
Remote Code Execution
Exploit Status
Not Exploited
Exploitation Likelihood
Less Likely
Patch Tuesday
2023-Sep
Released
2023-09-12
Last Updated
2023-09-14
EPSS Score
0.21% (percentile: 42.7%)

FAQ

How is the protection from this vulnerability applied? Microsoft Identity Linux Broker allows users with a Linux device support for bring your own device (BYOD) in an Azure AD environment. To be protected from this vulnerability you need to run the following command on the ubuntu machines: $ sudo apt update && sudo apt upgrade -y This will pull and update the released packages. You can find the packages here: Ubuntu 20.04 : Index of /ubuntu/20.04/prod/pool/main/m/microsoft-identity-broker Ubuntu 22.04: Index of /ubuntu/22.04/prod/pool/main/m/microsoft-identity-broker According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do? An attacker must send the user a malicious file and convince them to open it. According to the CVSS metric, the attack vector is local (AV:L). Why does the CVE title indicate that this is a remote code execution? The word Remote in the title refers to the location of the attacker. This type of exploit is sometimes referred to as Arbitrary Code Execution (ACE). The attack itself is carried out locally. This means an attacker or victim needs to execute code from the local machine to exploit the vulnerability. According to the CVSS metric, Confidentiality, and Integrity are Low (CI:L). What does that mean for this vulnerability? An attacker is only able to compromise files that they were allowed access to as part of their initial privilege. Any encrypted data will still be protected since the attacker doesn't have access to the Device Broker encryption key as part of this vulnerability.

Affected Products (1)

Azure

  • Microsoft Identity Linux Broker

Security Updates (2)

Acknowledgments

<a href="https://social.memes.nz/@jamie">Jamie McClymont</a> with <a href="https://cybercx.co.nz/">CyberCX</a>, Rhys Davies with <a href="https://cybercx.co.nz/">CyberCX</a>

Revision History

  • 2023-09-12: Information published.
  • 2023-09-14: Updated links to security updates. This is an informational change only.