vastlint
VAST-3.0-icon-height

VAST-3.0-icon-height

<Icon> missing required height attribute

ErrorRequired fieldsIAB VAST 3.0 §2.4.5VAST 3.0, 4.0, 4.1, 4.2, and 4.3

Short answer

height is required on <Icon> in VAST 3.0+.

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 3.0, 4.0, 4.1, 4.2, and 4.3.

How to fix

Add height with the icon's pixel height to <Icon>, e.g. height="15".

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