Redaction is an essential tool when certain parts of documents have to be kept classified while the rest can be read/ accessed by anybody. Redaction is a means of obliterating from unrestricted view information that cannot be shared with anyone and everyone just before a document is published officially. The major drawback of data redaction is that it is a complex technique and most people, even those in-charge of screening material, don't really know how to redact documents properly. Because of this, two seemingly avoidable mistakes are made frequently. The first is that most people simply hide information instead of deleting it entirely.
It should be obvious that if something is left within the document, however hidden, it can be accessed by someone who knows how. Another common oversight that people commit is that they fail to/ or don't know how to scan the document for text that might already be concealed, especially in the form of metadata, and hence they approve these documents for publishing, not realizing they're sending sensitive information forward.
On an average documents are made in regular formats like Microsoft PowerPoint and Microsoft Word after which they are turned into the PDF format for further processing. Electronic redaction is most effective when it is done at the writing stage itself, especially if it is done in the original application/ format of the document. In case a document has already been converted, PDF redaction software can be used to effectively sanitize PDF files.
From document masking, using redaction tool programs and redaction software and legal redaction, here are some of the general mistakes people make.
The biggest mistake people make is thinking if something is hidden from view, it cannot be accessed at all. People also try to conceal information by changing the color of the sensitive text and background to the same. Covering the controversial text with a differently colored, thick triangle is another technique. Highlighting the sensitive portions in black is a favorite with editors. Though these techniques are effective when one is trying to conceal material on paper, they are of little efficacy when it comes to electronic redaction such as PDF redaction.
Somebody who knows what they're looking for will know to extract information by undoing the color labeling/ highlighting. A redaction technique involves pasting innocuous graphics over sensitive text.
During the editing process, these images might slip away unnoticed. But for someone who is pursuing the sensitive information, the graphics simply have to be selected and deleted from the document.
Editors who're unaware of Meta-data or not sure of how to remove it will let the document get printed and thus sensitive content can be easily extracted.
With trying to Sanitize PDF files, the other common mistake is not being familiar with Meta data.