# CVE-2021-26829: OpenPLC ScadaBR Cross-site Scripting Vulnerability

> CVE-2021-26829: OpenPLC ScadaBR Cross-site Scripting Vulnerability. CVSS 5.4 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2021-26829
Last updated: 2025-12-02T04:56:04Z

- Published: 2021-06-11 11:05 UTC · Updated: 2025-12-02 04:56 UTC · Assigner: mitre
- CVSS: 5.4 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- EPSS: 48.1%, 99th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2025-11-28, federal due date 2025-12-19, ransomware use: Unknown

## Description

OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows allows stored XSS via system\_settings.shtm.

## CISA required action

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

## Affected vendors and products

- OpenPLC: ScadaBR

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-26829)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2021-26829)
- [http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4](http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4)
- [https://youtu.be/Xh6LPCiLMa8](https://youtu.be/Xh6LPCiLMa8)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2021-26829 · Markdown: https://rewindex.com/cve/CVE-2021-26829.md · JSON: https://rewindex.com/api/v1/cves/CVE-2021-26829 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:12:34.237Z