Is CVE-2021-26828 in the CISA KEV catalog?

Yes. CVE-2021-26828 is on the CISA Known Exploited Vulnerabilities list, added 2025-12-03.

What is the CVSS severity of CVE-2021-26828?

CVE-2021-26828 has a CVSS v3 base score of 8.8 (HIGH).

What is the EPSS score for CVE-2021-26828?

CVE-2021-26828 has an EPSS score of 39.36% (98th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2021-26828

HIGHCISA KEVEPSS 98th pctl

8.8

CVSS v3

NVD

Description

OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows allows remote authenticated users to upload and execute arbitrary JSP files via view_edit.shtm.

CWE-434Unrestricted File Upload

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploit Intelligence

39.36%probability of exploitation in 30 days

98thpercentile

Very high risk: more likely to be exploited than 98% of all known CVEs.

Known Exploited Vulnerability (CISA KEV)

OpenPLC ScadaBR Unrestricted Upload of File with Dangerous Type Vulnerability

OpenPLC ScadaBR contains an unrestricted upload of file with dangerous type vulnerability that allows remote authenticated users to upload and execute arbitrary JSP files via view_edit.shtm.

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Remediation due: 2025-12-24

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-12-04.