CVE-2021-33023

Advantech WebAccess

Description

Advantech WebAccess versions 9.02 and prior are vulnerable to a heap-based buffer overflow, which may allow an attacker to remotely execute code.

Remediation

Solution:

  • In order to address the heap-based buffer overflow vulnerability, Advantech recommends users directly add the remote access code to avoid being attacked by unknown requests. This is the remote access code established during installation of the Advantech WebAccess SCADA software (SCADA node, project node, or OPC Service) on the OPC Server computer. The access code you enter here must match the remote access code established during installation on the OPC Server. This prevents unauthorized users from accessing the OPC Server data using the Advantech WebAccess SCADA OPC Service. If you have forgotten the remote access code using during software installation on the OPC Server node, you have two options: Re-install the Advantech WebAccess SCADA software on the OPC Server node to change it and edit it to match in your database. Edit the BWSERVER.INI file on the OPC Server node and edit it to match in your database using UPDATE.

Categories

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.91% Top 30%
Third-Party Advisory cisa.gov
Affected: Advantech WebAccess
Published at:
Updated at:

References

Link Tags
https://us-cert.cisa.gov/ics/advisories/icsa-21-285-02 mitigation third party advisory us government resource

Frequently Asked Questions

What is the severity of CVE-2021-33023?
CVE-2021-33023 has been scored as a critical severity vulnerability.
How to fix CVE-2021-33023?
To fix CVE-2021-33023: In order to address the heap-based buffer overflow vulnerability, Advantech recommends users directly add the remote access code to avoid being attacked by unknown requests. This is the remote access code established during installation of the Advantech WebAccess SCADA software (SCADA node, project node, or OPC Service) on the OPC Server computer. The access code you enter here must match the remote access code established during installation on the OPC Server. This prevents unauthorized users from accessing the OPC Server data using the Advantech WebAccess SCADA OPC Service. If you have forgotten the remote access code using during software installation on the OPC Server node, you have two options: Re-install the Advantech WebAccess SCADA software on the OPC Server node to change it and edit it to match in your database. Edit the BWSERVER.INI file on the OPC Server node and edit it to match in your database using UPDATE.
Is CVE-2021-33023 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-33023 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-33023?
CVE-2021-33023 affects Advantech WebAccess.
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