How severe is CVE-2021-33000?

CVE-2021-33000 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33000 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33000?

CVE-2021-33000 affects Advantech Webaccess/hmi Designer. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33000?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-33000 published?

CVE-2021-33000 was published on 2021-06-24 and last updated on 2026-06-17.

CVE-2021-33000

CVE-2021-33000 is a high-severity vulnerability in Advantech Webaccess/hmi Designer with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Advantech Webaccess/hmi Designer
Published: 2021-06-24
Last modified: 2026-06-17

Description

Parsing a maliciously crafted project file may cause a heap-based buffer overflow, which may allow an attacker to perform arbitrary code execution. User interaction is required on the WebAccess HMI Designer (versions 2.1.9.95 and prior).

Frequently asked questions

What is CVE-2021-33000?: Parsing a maliciously crafted project file may cause a heap-based buffer overflow, which may allow an attacker to perform arbitrary code execution. User interaction is required on the WebAccess HMI Designer (versions 2.1.9.95 and prior).
How severe is CVE-2021-33000?: CVE-2021-33000 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33000 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33000?: CVE-2021-33000 affects Advantech Webaccess/hmi Designer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33000?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-33000 published?: CVE-2021-33000 was published on 2021-06-24 and last updated on 2026-06-17.

References

https://us-cert.cisa.gov/ics/advisories/icsa-21-173-01

Affected products (1)

cpe:2.3:a:advantech:webaccess\/hmi_designer:*:*:*:*:*:*:*:*

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