Web Bugs and Read Receipts in Emails and Attachments

Obviously you should always be suspicious of Email attachments and make sure that they are checked by up to date anti-virus software before you open them.

However there are other, more subtle ticks aimed at tracking and possibly identifying the recipients of emails, which have been used to attempt to uncover the identities of confidential journalistic sources etc.:

Web Bugs and Read Receipts in Emails and Attachments

A reminder that it is not just Governments who use their legal powers to snoop on journalists, campaign activists and bloggers, in order to try to identify their whistleblower anonymous sources:

The recent corporate scandal involving the giant Hewlett Packard computer corporation and its attempts to track down "leaks" to journalists, highlighted the use of webbugs
i.e. embedded images located on webservers directly under the control of a corporation or of a commercial tracking service such as the one used by Hewlett Packard, namely www.readnotify.com, which does have some legitimate uses, such as proof of delivery of legal documents etc. , by prior arrangement, but which can also be used to try to track down whistleblowers and their journalistic contacts.

ReadNotify also made use of Email Delivery Service Notifications (the standard optional internet email Read Receipts, and derivatives like the Microsoft Exchange email Deleted but nNot Read) and Message Disposition Notifications and IFRAMEs and graphic image web bugs embedded in Microsoft Office documents and Adobe .pdf email attachments.

See ReadNotify tracking journalists and their sources, or being used for disinformation ?

When a HTML email is opened, or a Microsoft Word or Excel or Powerpoint document or an Adobe .pdf document is opened, the client software can be made to pull an embedded image (very often a hard to see transparent 1 x 1 pixel graphic) from a remote internet webserver, thereby leaving IP address and browser details in that webserver's logfiles.

To protect yourself (and your "anonymous" whistleblower source) from such sneaky tracking, make sure that your email software is set to display messages as Plain Text and not to display Graphical Images by default.

Alternatively (or in addition) make sure that you disconnect from the internet temporarily when you open such an email and / or attached documents (many personal firewall software products e.g. ZoneAlarm have an "Internet connection" Off Switch"), or switch off your internet dial-up or ADSL connection when you open such attachments.

Alternatively, using something like Tor and Privoxy as described elsewhere in this guide, may be sufficient to confuse such tracking services about your real IP address and web browser type etc.

About this blog

We know that there are decent, honest, trustworthy individual politicians, civil servants, law enforcement, intelligence agency personnel and broadcast, print and internet journalists etc., who often feel powerless or trapped in the system. They need the assistance of external, detailed, informed, public scrutiny to help them to resist deliberate or unthinking policies, which erode our freedoms and liberties.

Some of these people will, in the public interest, act as whistleblowers, and may try to leak documents or information to the mainstream media, or to political blog websites etc.

Here are some Spy Blog "Hints and Tips", giving some basic preecautions, and some more obscure technical tips, which both whistleblowers, journalists, and bloggers need to be aware of, in order to help preserve the anonymity of whisteleblowing or other journalistic sources, especially in the United Kingdom, but applicable in other countries as well.

Whistleblower anonymity may not always be possible, or even necessary, forever into the future, but it is usuially crucial during at least the early stages of a "leak", whilst it is being evaluated by others, to see if it merits wider publication and publicity.

Email & PGP Contact

Please feel free to email your views about this blog, or news about the issues it tries to comment on.


Our PGP public encryption key is available for those correspondents who wish to send us news or information in confidence, and also for those of you who value your privacy, even if you have got nothing to hide.

You can download a free copy of the PGP encryption software from www.pgpi.org
(available for most of the common computer operating systems, and also in various Open Source versions like GPG).

We look forward to the day when UK Government Legislation, Press Releases and Emails etc. are Digitally Signed so that we can be assured that they are not fakes. Trusting that the digitally signed content makes any sense, is another matter entirely.


Tag Cloud

CryptoParty London

CryptoParty London

Most months there is a CryptoParty London event. where some of these Hints and Tips and other techniques are demonstrated and taught.

Usually at:

Juju's Bar and Stage 15 Hanbury St, E1 6QR, London

Follow on Twitter: @CryptoPartyLDN

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Campaign Button Links

Watching Them, Watching Us, UK Public CCTV Surveillance Regulation Campaign
UK Public CCTV Surveillance Regulation Campaign

NO2ID Campaign - cross party opposition to the NuLabour Compulsory Biometric ID Card
NO2ID Campaign - cross party opposition to the NuLabour Compulsory Biometric ID Card and National Identity Register centralised database.

Gary McKinnon is facing extradition to the USA under the controversial Extradition Act 2003, without any prima facie evidence or charges brought against him in a UK court. Try him here in the UK, under UK law.
Gary McKinnon is facing extradition to the USA under the controversial Extradition Act 2003, without any prima facie evidence or charges brought against him in a UK court. Try him here in the UK, under UK law.

FreeFarid.com- - Kafkaesque extradition of Farid Hilali under the European Arrest Warrant to Spain

Peaceful resistance to the curtailment of our rights to Free Assembly and Free Speech in the SOCPA Designated Area around Parliament Square and beyond

Parliament Protest blog - resistance to the Designated Area restricting peaceful demonstrations or lobbying in the vicinity of Parliament.

Petition to the European Commission and European Parliament against their vague Data Retention plans
Data Retention is No Solution Petition to the European Commission and European Parliament against their vague Data Retention plans.

Open Rights Group

renew for freedom - renew your passport in 2006
Renew For Freedom - renew your Passport in the Summer Autumn of 2006.

The Big Opt Out Campaign - opt out of having your NHS Care Record medical records and personal details stored insecurely on a massive national centralised database.

Tor - the onion routing network
Tor - the onion routing network - "Tor aims to defend against traffic analysis, a form of network surveillance that threatens personal anonymity and privacy, confidential business activities and relationships, and state security. Communications are bounced around a distributed network of servers called onion routers, protecting you from websites that build profiles of your interests, local eavesdroppers that read your data or learn what sites you visit, and even the onion routers themselves."

Tor - the onion routing network
Anonymous Blogging with Wordpress and Tor - useful Guide published by Global Voices Advocacy with step by step software configuration screenshots (updated March 10th 2009).

Amnesty International's irrepressible.info campaign

BlogSafer - wiki with multilingual guides to anonymous blogging

NGO in a box - Security Edition privacy and security software tools

Home Office Watch blog, "a single repository of all the shambolic errors and mistakes made by the British Home Office compiled from Parliamentary Questions, news reports, and tip-offs by the Liberal Democrat Home Affairs team."

Reporters Without Borders - Reporters Sans Frontières - campaign for journalists 'and bloggers' freedom in repressive countries and war zones.

Committee to Protect Bloggers - "devoted to the protection of bloggers worldwide with a focus on highlighting the plight of bloggers threatened and imprisoned by their government."

Wikileaks.org - the controversial "uncensorable, anonymous whistleblowing" website based currently in Sweden.

Public Concern at Work - "(PCaW) is the independent authority on public interest whistleblowing. Established as a charity in 1993 following a series of scandals and disasters, PCaW has played a leading role in putting whistleblowing on the governance agenda and in developing legislation in the UK and abroad. All our work is informed by the free advice we offer to people with whistleblowing dilemmas and the professional support we provide to enlightened organisations."