A system for preventing publication of an update to a web document, comprising: one or more processors; a computer readable medium storing instructions that, when executed by the one or more processors, cause the system to perform operations comprising: accessing a published web document comprising a plurality of distinct elements (402,404,406) generated using data received from a computing device of a user, wherein the web document is assigned a URI that uniquely identifies the web document; accessing an updated web document, the updated web document being based on one or more modifications to the published web document made by the user using an interface presented on a computing device of the user, the updated web document including at least one user generated modification to a distinct element of the plurality of distinct elements (402,404,406) of the published web document, wherein the published web document and the updated web document are assigned the same URI; generating one or more anomaly scores based on a comparison of individual parts of the updated web document to corresponding parts of the published web document, wherein the anomaly scores include an aggregate anomaly score that aggregates a text match score, an image similarity score and a numerical deviation score; and determining whether to allow publication of the updated web document, based on a result of a comparison of the aggregate anomaly score to a threshold anomaly score, and preventing publication of the updated web document in response to the aggregate anomaly score transgressing the threshold anomaly score. one or more processors; a computer readable medium storing instructions that, when executed by the one or more processors, cause the system to perform operations comprising: accessing a published web document comprising a plurality of distinct elements (402,404,406) generated using data received from a computing device of a user, wherein the web document is assigned a URI that uniquely identifies the web document; accessing an updated web document, the updated web document being based on one or more modifications to the published web document made by the user using an interface presented on a computing device of the user, the updated web document including at least one user generated modification to a distinct element of the plurality of distinct elements (402,404,406) of the published web document, wherein the published web document and the updated web document are assigned the same URI; generating one or more anomaly scores based on a comparison of individual parts of the updated web document to corresponding parts of the published web document, wherein the anomaly scores include an aggregate anomaly score that aggregates a text match score, an image similarity score and a numerical deviation score; and determining whether to allow publication of the updated web document, based on a result of a comparison of the aggregate anomaly score to a threshold anomaly score, and preventing publication of the updated web document in response to the aggregate anomaly score transgressing the threshold anomaly score. accessing a published web document comprising a plurality of distinct elements (402,404,406) generated using data received from a computing device of a user, wherein the web document is assigned a URI that uniquely identifies the web document; accessing an updated web document, the updated web document being based on one or more modifications to the published web document made by the user using an interface presented on a computing device of the user, the updated web document including at least one user generated modification to a distinct element of the plurality of distinct elements (402,404,406) of the published web document, wherein the published web document and the updated web document are assigned the same URI; generating one or more anomaly scores based on a comparison of individual parts of the updated web document to corresponding parts of the published web document, wherein the anomaly scores include an aggregate anomaly score that aggregates a text match score, an image similarity score and a numerical deviation score; and determining whether to allow publication of the updated web document, based on a result of a comparison of the aggregate anomaly score to a threshold anomaly score, and preventing publication of the updated web document in response to the aggregate anomaly score transgressing the threshold anomaly score.