OpenSearch Dashboards TSVB prototype pollution RCE
OpenSearch Dashboards TSVB prototype pollution RCE. Upgrade to the patched release.
Also tracked as CVE-2026-18420
First observed
Aug 21, 2026
Last observed
Aug 21, 2026
Last reviewed
Sep 20, 2026
Tracking ended
Aug 21, 2026
Uncertainty and limitations
Read the evidence limits before acting on this record.
Confirm exact fixed version against the live advisory.
- Campaign tracks CVE-2026-18420 only.
- HOL blog is operator guidance.
Timeline
Reviewed events, oldest first, each tied to a verified source.
- Disclosure
CVE-2026-18420 OpenSearch Dashboards TSVB RCE disclosed.
- Update
HOL Guard published operator coverage.
Publication clock: 739.0 hours from reviewed disclosure timestamp to HOL publication; 24-hour high target; historical backfill outside target.
Guard coverage and non-coverage
What Guard's reviewed coverage assertions do and do not claim for this campaign.
No Guard coverage mapping is published for this record.
Defensive policy guidance
Reviewed starting points for defending against this campaign's artifact classes.
No campaign-specific policy guidance is published.
Sources
Every claim on this record is traceable to the sources below.
Reviewed in full by HOL Guard Security Publishing.
- Published
- Last full review
- Last modified
Record HGTC-2026-37B1F358.