vastlint
VAST-4.1-exec-resource-type

VAST-4.1-exec-resource-type

<ExecutableResource> is missing required type attribute

ErrorRequired fieldsIAB VAST 4.1 §2.3VAST 4.1, 4.2, and 4.3

Short answer

type is required on <ExecutableResource> in VAST 4.1+. It identifies the executable format.

Why this matters in production

This rule is usually a delivery blocker. Many players, SDKs, and ad servers will discard the response or skip the affected creative once this condition is hit. Required-field failures usually stop validation early because the platform cannot determine the basic shape of the ad, the creative metadata, or the mandatory tracking payload. Affected scope: VAST 4.1, 4.2, and 4.3.

How to fix

Add type="application/javascript" (or the appropriate executable format type) to <ExecutableResource>.

Check your VAST tag for VAST-4.1-exec-resource-type and other issues instantly.Validate a tag →