Advisory Details

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Advantech WebAccess/HMI Designer. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.

The specific flaw exists within the parsing of SNF files. The issue results from the lack of proper validation of user-supplied data, which can result in a memory corruption condition. An attacker can leverage this vulnerability to execute code in the context of the current process.

This vulnerability is being disclosed publicly without a patch in accordance with the ZDI 120 day deadline.

12/02/20 – ZDI reported the vulnerability to ICS-CERT
04/02/21 – ICS-CERT indicated the vendor was working on a fix
04/06/21 – ZDI requested an update
04/06/21 – ICS-CERT indicated the vendor was working on a fix
04/08/21 – ZDI notified ICS-CERT of the intention to publish the case as a 0-day advisory on 04/20/21

-- Mitigation:
Given the nature of the vulnerability the only salient mitigation strategy is to restrict interaction with the application.

• 2020-12-02 - Vulnerability reported to vendor
• 2021-06-24 - Coordinated public release of advisory