CVE-2026-662988.6HighCWE-346

CVE-2026-66298: JS-view sandboxed output can synthesize keyboard events to trigger unconfirmed global shortcuts

livebook-dev · livebook

Vendor fix available · Affected: livebook-dev · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.3%probability of exploitation in the next 30 days

19th percentile

050100

Higher than 19% of scored CVEs

8.6HighCVSS 4.0

LowMediumHighCrit.

DescriptionCVE.org

Origin Validation Error vulnerability in livebook-dev livebook allows untrusted notebook output JavaScript to trigger session-wide keyboard shortcuts, including forced evaluation of all cells and runtime restart. Livebook's JS-view feature renders notebook-defined JavaScript inside a sandboxed, cross-origin iframe specifically because that JavaScript is untrusted. The trusted iframe shell in iframe/priv/static/iframe/v5.html forwards every keydown event fired in its own window to the parent page without consulting Event.isTrusted, so an event synthesized by the untrusted script through window.dispatchEvent is forwarded exactly as a genuine keystroke would be. The parent-side relay in assets/js/hooks/js_view.js reconstructs and re-dispatches it on the live page with no further validation, and because assets/js/hooks/session.js registers the global shortcut handler on the document in the capture phase, that handler acts on the replicated event regardless of how it was produced. Sandboxed output JavaScript can therefore drive Livebook's session-wide keyboard shortcuts. Two of them reach LivebookWeb.SessionLive and execute immediately with no confirmation: the shortcut for queueing full evaluation runs every cell in the notebook, and the shortcut for reconnecting the runtime disconnects and reconnects it, discarding in-memory state. A third shortcut deletes the focused cell behind a confirmation dialog that the user can permanently dismiss, after which it too executes silently. Forced full evaluation is the significant consequence, because it causes the notebook's own Elixir code to run without the user choosing to evaluate anything. A user who merely opens a notebook obtained from a third party, or reached from published documentation, can have its code executed on their runtime. Livebook also mirrors cell outputs to every connected client, so a malicious output triggers in a collaborator's browser as soon as it renders.

Affected products3

From the CVE record. A product or version that is not listed is unknown, not unaffected.

livebook-dev · livebookfrom 0.5.0 before 0.18.7; from 0.19.0 before 0.19.9
livebook-dev · livebookfrom 0.5.0 before 0.18.7; from 0.5.0-cuda12 before 0.18.7-cuda12; from 0.19.0 before 0.19.9; from 0.19.0-cuda12 before 0.19.9-cuda12
livebook-dev · livebookVersions not stated

On the Atlas

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Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Origin Validation Error · Access Control
Vendor: livebook-dev
Published: August 2026
Band: Unlikely (under 1%), August 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-66298 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.