VASTlint
VMAP-1.0-customaddata-cdata

VMAP-1.0-customaddata-cdata

`<CustomAdData>` data must be contained within a CDATA block

ErrorVMAPIAB VMAP 1.0.1 §2.3.2VMAP 1.0 (all VMAP documents)

Short answer

The content of <CustomAdData> must be wrapped in a CDATA section to prevent XML parsers from interpreting markup characters inside the payload.

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. VMAP rules validate the ad break schedule envelope. Malformed break timing, wrong namespace declarations, or invalid AdSource content prevent players from resolving any of the ads in the playlist. Affected scope: VMAP 1.0 (all VMAP documents).

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