CVE-2026-55839 (GCVE-0-2026-55839)

Vulnerability from cvelistv5 – Published: 2026-08-18 15:27 – Updated: 2026-08-18 17:46
VLAI
Title
Kestra: Stored XSS via custom Markdown [[link]] attribute injection
Summary
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.
Severity
8.7 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-18 17:28 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8120 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
kestra-io kestra Affected: < 1.3.24
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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