OpenPLC ScadaBR Cross-site Scripting Vulnerability
OpenPLC ScadaBR contains a cross-site scripting vulnerability via system_settings.shtm.
- Vendor
- OpenPLC
- Product
- ScadaBR
- CVSS
- 5.4
- EPSS (exploit probability)
- 48.0%
- Status
- kev
- CISA patch-by (BOD 22-01)
- Added to KEV
Is CVE-2021-26829 being exploited?
Yes. CISA added CVE-2021-26829 to its Known Exploited Vulnerabilities catalog on . CISA only lists a CVE when it has reliable evidence of exploitation in the wild.
FIRST's EPSS model puts the probability of exploitation activity in the next 30 days at 48.0% (scored October 14, 2026).
- CISA KEV[ LISTED ]
- ENISA EUVD (exploited)[ — ]
- CIRCL KEV[ — ]
Catalog snapshot 2026-10-23. Full cross-catalog view: /kev-comparison
CVE-2021-26829 timeline
Every event links to its source. Catalog dates are each catalog's own; day offsets count from NVD publication. Data: JSON
What to do
CISA required actionApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
US federal civilian agencies must remediate by (21 days after listing) under BOD 22-01. Everyone else: that deadline is a sensible upper bound, not a target. Vendor guidance and the NVD record are linked under Source above.
Other OpenPLC CVEs we track
| CVE / Vulnerability | Severity | CVSS | EPSS | Added to KEV |
|---|---|---|---|---|
| CVE-2021-26828 OpenPLC ScadaBR Unrestricted Upload of File with Dangerous Type Vulnerability | [ HIGH ] | 8.8 | 39.1% |