How severe is CVE-2026-9853?

CVE-2026-9853 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-9853 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-9853?

CVE-2026-9853 affects Hitachienergy Microscada X Sys600. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-9853?

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-2026-9853 published?

CVE-2026-9853 was published on 2026-09-03 and last updated on 2026-09-09.

CVE-2026-9853

CVE-2026-9853 is a high-severity vulnerability in Hitachienergy Microscada X Sys600 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-303.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v4: 8.5
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-303
Affected product: Hitachienergy Microscada X Sys600
Published: 2026-09-03
Last modified: 2026-09-09

Description

A vulnerability exists in SYS600 which allows any user authenticated to the operating system of the server hosting the application to read and modify application objects without being authenticated to the SYS600 system itself. Only the SYS600 system users should be permitted to view and modify application objects.

Frequently asked questions

What is CVE-2026-9853?: A vulnerability exists in SYS600 which allows any user authenticated to the operating system of the server hosting the application to read and modify application objects without being authenticated to the SYS600 system itself. Only the SYS600 system users should be permitted to view and modify application objects.
How severe is CVE-2026-9853?: CVE-2026-9853 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-9853 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-9853?: CVE-2026-9853 affects Hitachienergy Microscada X Sys600. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-9853?: 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-2026-9853 published?: CVE-2026-9853 was published on 2026-09-03 and last updated on 2026-09-09.

References

https://publisher.hitachienergy.com/preview?DocumentID=8DBD000249&LanguageCode=en&DocumentPartId=&Action=Launch

Affected products (1)

cpe:2.3:a:hitachienergy:microscada_x_sys600:*:*:*:*:*:*:*:*

More vulnerabilities in Hitachienergy Microscada X Sys600

CVE-2024-4872 — Critical (CVSS 9.9): A vulnerability exists in the query validation of the MicroSCADA Pro/X SYS600 product. If exploited this could allow an…
CVE-2024-3980 — Critical (CVSS 9.9): The MicroSCADA Pro/X SYS600 product allows an authenticated user input to control or influence paths or file names that…
CVE-2022-3388 — High (CVSS 8.8): An input validation vulnerability exists in the Monitor Pro interface of MicroSCADA Pro and MicroSCADA X SYS600. An…
CVE-2022-29490 — High (CVSS 8.5): Improper Authorization vulnerability exists in the Workplace X WebUI of the Hitachi Energy MicroSCADA X SYS600 allows…
CVE-2024-7940 — High (CVSS 8.3): The product exposes a service that is intended for local only to all network interfaces without any authentication.
CVE-2024-3982 — High (CVSS 8.2): An attacker with local access to machine where MicroSCADA X SYS600 is installed, could enable the session logging…

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