How severe is CVE-2026-28205?

CVE-2026-28205 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-2026-28205 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-28205?

CVE-2026-28205 affects Openplcproject Openplc V3 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-28205?

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.

Does CVE-2026-28205 have an EU (EUVD) identifier?

Yes. CVE-2026-28205 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21009.

When was CVE-2026-28205 published?

CVE-2026-28205 was published on 2026-04-09 and last updated on 2026-06-17.

CVE-2026-28205

CVE-2026-28205 is a critical-severity vulnerability in Openplcproject Openplc V3 Firmware 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-1188.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 9.2
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-21009
Weakness: CWE-1188
Affected product: Openplcproject Openplc V3 Firmware
Published: 2026-04-09
Last modified: 2026-06-17

Description

OpenPLC_V3 is vulnerable to an Initialization of a Resource with an Insecure Default vulnerability which could allow an attacker to gain access to the system by bypassing authentication via an API.

Frequently asked questions

What is CVE-2026-28205?: OpenPLC_V3 is vulnerable to an Initialization of a Resource with an Insecure Default vulnerability which could allow an attacker to gain access to the system by bypassing authentication via an API.
How severe is CVE-2026-28205?: CVE-2026-28205 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-2026-28205 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-28205?: CVE-2026-28205 affects Openplcproject Openplc V3 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-28205?: 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.
Does CVE-2026-28205 have an EU (EUVD) identifier?: Yes. CVE-2026-28205 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21009.
When was CVE-2026-28205 published?: CVE-2026-28205 was published on 2026-04-09 and last updated on 2026-06-17.

References

https://www.cisa.gov/news-events/ics-advisories/icsa-25-345-10

Affected products (1)

cpe:2.3:o:openplcproject:openplc_v3_firmware:-:*:*:*:*:*:*:*

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