Back to vendor advisories
AWS Security BulletinsCVE-2026-5429

CVE-2026-5429 - Kiro IDE Webview Cross-Site Scripting via Workspace Color Theme

Bulletin ID: 2026-012-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 2026/04/02 11:30 AM PDT Description: Kiro IDE is an agentic development environment that makes it easy for developers to ship real engineering work with the help of AI agents. We identified CVE-2026-5429, where unsanitized input during web page generation in the Kiro Agent webview in Kiro IDE before version 0.8.140 allows a remote unauthenticated threat actor to execute arbitrary code via a maliciously crafted color theme name when a local user opens the workspace. This issue requires the user to trust the workspace when prompted. Impacted versions: < 0.8.140 Please refer to the article below for the most up-to-date and complete information related to this AWS Security Bulletin.

Not listedCVSS not listedNot listed severity
Scope

What the vendor says is affected

The collected bulletin did not provide a separate affected-products list. Check the original bulletin before making an exposure decision.

Update history

What changed in later vendor updates

SecurityAlert records field-level changes from the point we begin following a bulletin. Earlier vendor changes may not have a field-by-field record.

    • The vendor changed the advisory's last-updated date.
Timeline

When this advisory changed

  1. Added to SecurityAlert

    We collected the advisory from the official source.

  2. Published by AWS

    The publication date reported by the vendor.

  3. Confirmed at the source

    Our collector saw this advisory during a later source check.

Vulnerabilities

CVEs named in this advisory