CVE-2026-55839: Kestra-Io Kestra

High severity, CVSS 8.7. EPSS: 0.4% chance of exploitation in the next 30 days.

Kestra is an open-source, event-driven orchestration platform. Prior to 1.3.24, Kestra's custom Markdown parser in ui/src/utils/markdown_plugins/link.ts allows a user with permission to create or update a Flow description to inject JavaScript event-handler attributes through the custom [[link]] syntax, causing stored cross-site scripting when another user opens the description or information panel in the Flow list. This issue is fixed in version 1.3.24.

Affected products

• Kestra-Io Kestra: before 1.3.24 (fixed in 1.3.24)

Published 2026-08-18. Last modified 2026-09-16.