CVE-2026-33664: Kestra Vulnerable to Stored Cross-Site Scripting via Flow YAML Fields
Kestra is an open-source, event-driven orchestration platform Versions up to and including 1.3.3 render user-supplied flow YAML metadata fields — description, inputs[].displayName, inputs[].description — through the Markdown.vue component instantiated with html: true. The resulting HTML is injected into the DOM via Vue's v-html without any sanitization. This allows a flow author to embed arbitrary JavaScript that executes in the browser of any user who views or interacts with the flow. This is distinct from GHSA-r36c-83hm-pc8j / CVE-2026-29082, which covers only FilePreview.vue rendering .md files from execution outputs. The present finding affects different components, different data sources, and requires significantly less user interaction (zero-click for input.displayName). As of time of publication, it is unclear if a patch is available.
Metrics
- CVSS v3.1
- 7.3
- Severity
- HIGH
- Fixed in
- —
- Affected Products
- 1
- kestra-io / kestra<= 1.3.3
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N