Ministry of Defence fails at redacting nuclear sub secrets

The UK's Ministry of Defence is reported to have failed to correctly redact PDF files it released under the Freedom of Information Act. Redaction is the process of removing classified information from documents; on paper documents, this is done by using a black marker to cross out the text. The report in question, "SUCCESSOR SSBN - SAFETY REGULATORS ADVICE ON THE SELECTION OF THE PROPULSION POLANT IN SUPPORT OF THE FUTURE DETERRENT REVIEW NOTE" was published as a PDF file on the parliamentary site, the Daily Star revealed the MoD had originally "redacted" the document by changing the background colour of the text to black.

This meant that the document could be read by simply selecting the "redacted" areas and copy-and-pasting the still present text into a text editor. According to Cryptome, the text was also revealed by Google as it automatically scanned the document and converted it into HTML. In this case the document contained information about emergency procedures on UK nuclear submarines and the equivalent procedures on US submarines.

Graham Cluley of Sophos was quoted as asking "If this document is like this, who knows what else is?" The answer came on Sunday when a report in the Daily Telegraph revealed that other documents from the MoD, Department for Trade and Investment, Department of Health and the Department of Communities and Local Government suffered from incorrectly or insufficiently applied redaction. The MoD has started a review of currently published documents to fix the bad redactions. A guide on properly redacting PDF documents is available from Adobe.

(djwm)