How severe is CVE-2019-3940?

CVE-2019-3940 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-3940 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-3940?

CVE-2019-3940 affects Advantech Webaccess. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-3940?

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

When was CVE-2019-3940 published?

CVE-2019-3940 was published on 2019-04-09 and last updated on 2026-06-17.

CVE-2019-3940

CVE-2019-3940 is a critical-severity vulnerability in Advantech Webaccess with a CVSS 3.x base score of 9.8. 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-434.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Advantech Webaccess
Published: 2019-04-09
Last modified: 2026-06-17

Description

Advantech WebAccess 8.3.4 is vulnerable to file upload attacks via unauthenticated RPC call. An unauthenticated, remote attacker can use this vulnerability to execute arbitrary code.

Frequently asked questions

What is CVE-2019-3940?: Advantech WebAccess 8.3.4 is vulnerable to file upload attacks via unauthenticated RPC call. An unauthenticated, remote attacker can use this vulnerability to execute arbitrary code.
How severe is CVE-2019-3940?: CVE-2019-3940 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-3940 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-3940?: CVE-2019-3940 affects Advantech Webaccess. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-3940?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2019-3940 published?: CVE-2019-3940 was published on 2019-04-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:advantech:webaccess:8.3.4:*:*:*:*:*:*:*

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