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B&R has a rigorous internal cyber security continuous improvement process which involves regular testing with industry leading tools and periodic assessments to identify potential product issues. Occasionally an issue is determined to be a design or coding flaw with implications that may impact product cyber security.
When a potential product vulnerability is identified or reported, B&R immediately initiates our vulnerability handling process. This entails validating if the issue is in fact a product issue, identifying root causes, determining what related products may be impacted, developing a remediation, and notifying end users and governmental organizations.
The resulting Cyber Security Advisory intends to notify customers of the vulnerability and provide details on which products are impacted, how to mitigate the vulnerability or explain workarounds that minimize the potential risk as much as possible. The release of a Cyber Security Advisory should not be misconstrued as an affirmation or indication of an active threat or ongoing campaign targeting the products mentioned here. If B&R is aware of any specific threats, it will be clearly mentioned in the communication.
The publication of this Cyber Security Advisory is an example of B&R’s commitment to the user community in support of this critical topic. Responsible disclosure is an important element in the chain of trust we work to maintain with our many customers. The release of an Advisory provides timely information which is essential to help ensure our customers are fully informed.

Affected products

B&R Automation Runtime < I4.93

Vulnerability IDs



An update is available that resolves some internally reported vulnerabilities in the product versions listed above.

An unauthenticated network attacker who successfully exploited this vulnerability could run man-in-the- middle attacks or to decrypt communications between the affected products and other parties.

Recommended immediate actions

The problem is corrected in the following product versions:

B&R Automation Runtime version I4.93

B&R recommends that customers apply the update at earliest convenience.

The process to install updates is described in the user manual. The step to identify the installed product version is described in the user manual.

Vulnerability severity and details

A vulnerability exists in the FTP server component included in the product versions listed above. An un- authenticated network-based attacker who successfully exploited this vulnerability could run man-in- the-middle attacks or to decrypt communications between the affected products and other parties.

The severity assessment has been performed by using the FIRST Common Vulnerability Scoring System (CVSS) v3.11.

CVE-2024-0323 – FTP uses unsecure encryption mechanism in B&R Automation Runtime

The FTP server used on the B&R Automation Runtime supports unsecure encryption mechanisms, such as SSLv3, TLSv1.0 and TLS1.1. An network-based attacker can exploit the flaws to conduct man-in-the- middle attacks or to decrypt communications between the affected product clients.

CVSS v3.1 Base Score:        9.8 (Critical) CVSS v3.1 Temporal Score:    9.1 (Critical)

CVSS v3.1 Vector:                                   CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

NVD Summary Link: 

Mitigating factors

Refer to section “General security recommendations” for further advise on how to keep your system se- cure.

Frequently asked questions

What is the scope of the vulnerability?

An unauthenticated network attacker who successfully exploited this vulnerability could run man-in-the- middle attacks or to decrypt communications between the affected products and other parties.

What causes the vulnerability?

The vulnerability is caused by supporting the following obsolete SSL/TLS versions: SSLv3, TLSv1.0 and TLSv1.1 in the Automation Runtime.

What is B&R Automation Runtime?

B&R Automation Runtime (AR) is a real time operating system running on all B&R target systems.

What might an attacker use the vulnerability to do?

An unauthenticated network-based attacker who successfully exploited this vulnerability could run man- in-the-middle attacks or to decrypt communications between the affected products and other parties.

How could an attacker exploit the vulnerability?

An attacker could try to exploit the vulnerability by creating a specially crafted message and sending the message to an affected system node. This would require that the attacker has access to the system net- work, by connecting to the network either directly or through a wrongly configured or penetrated fire- wall, or that he installs malicious software on a system node or otherwise infects the network with mali- cious software.

Could the vulnerability be exploited remotely?

Yes, an attacker who has network access to an affected system node could exploit this vulnerability. Rec- ommended practices include that process control systems are physically protected, have no direct con- nections to the Internet, and are separated from other networks by means of a firewall system that has a minimal number of ports exposed.

What does the update do?

The update removes the vulnerability by modifying the way that the Automation Runtime uses SSL/TLS and corresponding cipher suites.

When this security advisory was issued, had this vulnerability been publicly disclosed?

No, B&R received information about this vulnerability through responsible disclosure.

When this security advisory was issued, had B&R received any reports that this vulnerability was being exploited?

No, B&R had not received any information indicating that this vulnerability had been exploited when this security advisory was originally issued.

General security recommendations

For any installation of software-related B&R products we strongly recommend the following (non-ex- haustive) list of cyber security practices:

  • Isolate special purpose networks (e.g. for automation systems) and remote devices behind firewalls and separate them from any general purpose network (e.g. office or home networks).
  • Install physical controls so no unauthorized personnel can access your devices, components, periph- eral equipment, and networks.
  • Never connect programming software or computers containing programing software to any net- work other than the network for the devices that it is intended for.
  • Scan all data imported into your environment before use to detect potential malware infections.
  • Minimize network exposure for all applications and endpoints to ensure that they are not accessible from the Internet unless they are designed for such exposure and the intended use requires such.
  • Ensure all nodes are always up to date in terms of installed software, operating system and firmware patches as well as anti-virus and firewall.
  • When remote access is required, use secure methods, such as Virtual Private Networks (VPNs). Rec- ognize that VPNs may have vulnerabilities and should be updated to the most current version availa- ble. Also, understand that VPNs are only as secure as the connected devices.


B&R thanks ABB Device Security Assurance Center for reporting this issue.


For additional instructions and support please contact your local B&R service organization. For contact information, see

Information about ABB’s cyber security program and capabilities can be found at security.

Version history

Rev. Ind.Page (p) Chapter (c)Change descriptionVersion. date
1.0allInitial version