The return of the Evil bit?

Firewalls, packet filters, intrusion detection systems, and the like often have difficulty distinguishing between packets that have malicious intent and those that are merely unusual. We define a security flag in the IPv4 header as a means of distinguishing the two cases.

How is this achieved?

To solve this problem, we define a security flag, known as the "evil" bit, in the IPv4 [RFC791] header. Benign packets have this bit set to 0; those that are used for an attack will have the bit set to 1.

But what happens if an evil application refuses to co-operate and leaves the evil bit reset on packets generated by it?

RFC3514 has a submission date of 01 April 2003, but this does not:

Microsoft Office 2003 introduced Information Rights Management (IRM) that provides a way to help restrict recipients from copying, printing, or forwarding e-mail messages.
[...]
Opening the message with other e-mail applications or even using different types of accounts might result in recipients having full permissions to forward or reply all to a message.

D’oh? I’ve heard of security by obscurity, but what do you call this? Security by divine fiat? Security by Redmond insists?

Comments

new life for an old (FTX) PSU, improved life for one human

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every-application-is-part-of-a-toolkit at work

I have a LibreOffice Impress slideshow that I wish to turn into a narrated video. 1. export the slideshow as PNG images (if that is partially broken — as at now — at higher resolutions, Export Directly as PDF then use ‘pdftoppm’ (from the poppler-utils package) to do the same). 2. write a small C program (63 lines including comments) to display those images one at a time, writing a config file entry for Imagination (default transition: ‘cross fade’) based on when the image-viewer application (‘display,’ from the GraphicsMagick suite) is closed on each one; run that, read each image aloud, then close each image in turn. 3. run ‘Imagination’ over the config file to produce a silent MP4 video with the correct timings. 4. run ‘Audacity’ to record speech while using ‘SMPlayer’ to display the silent video, then export that recording as a WAV file. 4a. optionally, use ‘TiMIDIty’ to convert a non-copyright-encumbered MIDI tune to WAV, then import that and blend it with the speech (as a quiet b...

boundaries

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Plantagenet Penguinista

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