XSS in Opensearch Dashboards Dashboards-Observability Plugin

CVE-2026-77811

Improper input validation in the dashboards-observability plugin in OpenSearch Dashboards allows a remote authenticated user with write permissions to OpenSearch Dashboards saved objects to execute arbitrary JavaScript in the context of other users' browser sessions by uploading a saved asset with arbitrary web content.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.005 (42.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-77811: held from 0.004 to 0.005.

EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-77811?
CVE-2026-77811 is a high-severity vulnerability in Opensearch Dashboards Dashboards-Observability Plugin, classified under Cross-site Scripting. CVSS score: 8.7/10. Published 2026-08-21.
How severe is CVE-2026-77811?
High severity. CVSS v3 base score is 8.7 out of 10.