Vulnerability Analysis
Kestra: Stored XSS via custom Markdown [[link]] attribute injection
CVE-2026-55839
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.
Cross-Site Scripting (XSS)
No Active Exploit Signals
CVSS Base Score
8.7
HIGH
Exploitability:2.3
Impact Score:5.8
Temporal Score:-
EPSS:-
Threat Intelligence Signals
CISA KEV
No
KEV Date Added
—
Ransomware Use
—
KEV Due Date
—
VulnCheck In-the-Wild
No
Nuclei Template
No
EPSS Score
—
EPSS Percentile
—
GHSA ID
GitHub Severity
HIGH
SSVC Exploitation
None
SSVC Automatable
No
Vulnerability Class
Cross-Site Scripting (XSS)
Identity & Timeline
| Status | - |
| Assigning Authority | - |
| Discovered Via | - |
| Record Completeness | - |
| CVSS Version / Source | - |
| Reserved | - |
| Published | - |
| Patch Date (date_public) | - |
| Exploit DB Date | - |
| First GitHub PoC Date | - |
| Last Updated | - |
| Time to Patch (Days to fix) | - |
| Exploit Release Gap | - |
| PoC Release Gap | - |
| Exploit DB References | None identified |
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| No affected products specified. | ||
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