TUCoPS :: Hardware Hacks :: datatapp.txt

Tapping computers for data - TEMPEST



Dec 27 21:24 1985  data.tap Page 1


--FEATURE ARTICLES AND REVIEWS-


 TAPPING COMPUTER DATA IS EASY, AND CLEARER THAN PHONE CALLS !

    BY RIC BLACKMON, SYSOP OF A FED BBS
        Aquired by Lunatic Labs
        Uploaded by Elric of Imrryr
-------------------------------

        FOR SEVERAL YEARS, I ACCEPTED CERTAIN BITS OF MISINFORMATION
AS TECHNICALLY ACCURATE, AND DIDN'T PROPERLY PURSUE THE  MATTER. SEVERAL
FOOLS GAVE ME FOOLISH INFORMATION, SUCH AS:
 A TAP INTERRUPTS COMPUTER DATA TRANSMISSIONS; DATA COULD BE PICKED UP
AS RF EMANATIONS BUT IT WAS A MASS OF UNINTELLIGIBLE SIGNAL CAUSED BY DATA 
MOVING BETWEEN REGISTERS; ONE HAD TO BE IN 'SYNC' WITH ANY SENDING COMPUTER;
DATA COULDN'T BE READ UNLESS YOU HAD A DIRECT MATCH IN SPEED, PARITY & BIT
PATTERN; AND ONLY A COMPUTER OF THE SAME MAKE AND MODEL COULD READ THE
SENDING COMPUTER. THIS IS ALL PLAIN SWILL. IT IS IN FACT, AN EASIER CHORE
TO TAP A COMPUTER THAN A TELEPHONE. THE TECHNIQUE AND THE EQUIPMENT IS ALMOST 
THE SAME,  BUT THE COMPUTER LINE WILL BE MORE ACCURATE (THE TWO COMPUTERS
INVOLVED, HAVE ERROR CORRECTING PROCEDURES) AND CLEARER (DIGITAL
TRANSMISSIONS HAVE MORE DISTINCT SIGNALS THAN ANALOG TRANSMISSIONS).

FIRST, RECOGNIZE THAT NEARLY ALL DATA TRANSMISSIONS ARE SENT IN CLEARTEXT
ASCII SIGNALS. THE LINES CARRYING OTHER BIT-GROUPS OR ENCYPHERED TEXTS ARE
RARE. SECOND, THE SIGNAL APPEARS ON GREEN AND RED (WIRES) OF THE PHONE LINE
('TIP' AND 'RING'). THE DATA IS MOST LIKELY ASYSCHRONOUS SERIAL DATA MOVING
AT 300 BAUD. NOW THAT 1200 BAUD IS BECOMING MORE CHIC, YOU CAN EXPECT TO
FIND A GROWING USE OF THE FASTER 
TRANSMISSION RATE. FINALLY, YOU DON'T NEED TO WORRY ABOUT THE PROTOCOL OR 
EVEN THE BAUD RATE(SPEED) UNTIL AFTER A TAPED COPY OF A TRANSMISSION IS 
OBTAINED.

        IN A SIMPLE EXPERIMENT, A TAPED COPY OF A DATA TRANSMISSION WAS MADE
WITH THE CHEAPEST OF TAPE RECORDERS, TAPPING THE GREEN  AND RED LINES BEYOND
THE MODEM. THE RECORDING WAS THEN PLAYED INTO A MODEM AS THOUGH IT WERE AN
ORIGINAL TRANSMISSION. AT THAT POINT, HAD IT BEEN NECESSARY, THE PROTOCOL 
SETTINGS ON RECEIVING TERMINAL COULD HAVE BEEN CHANGED TO MATCH THE TAPE. NO
ADJUSTMENTS WERE NECESSARY  AND A NICE, CLEAR ERROR-FREE DOCUMENT WAS RECEIVED
ON THE ILLICIT VIDEO SCREEN AND A NEAT HARD-COPY OF THE DOCUMENT CAME OFF THE
PRINTER. THE MESSAGE  WAS INDEED CAPTURED, BUT HAD IT BEEN AN
INTERCEPTION INSTEAD OF A SIMPLE MONITORING, IT COULD HAVE BEEN ALTERED
WITH A SIMPLE WORD PROCESSOR PROGRAM, TO SUIT ANY PURPOSE, AND PLACED BACK ON
THE WIRE.

        WERE I TO HAVE AN INTEREST IN INFORMATION ORIGINATING FROM A 
PARTICULAR COMPANY, AGENCY, OR OFFICE, I THINK THAT I WOULD FIND IT FAR MORE
PRODUCTIVE TO TAP A DATA TRANSMISSION THAN TO TAP A VOICE TRANSMISSION, AND
EVEN MORE REWARDING THAN GETTING HARDCOPY DOCUMENTS.

        *SIGNIFICANT & IMPORTANT INFORMATION IS MORE CONCENTRATED IN A
DATA TRANSMISSION.
        *SIGNIFICANT & IMPORTANT INFORMATION IS MORE EASILY LOCATED IN 
DATA TRANSMISSIONS THAN IN MASSES OF FILES OR PHONE CALLS.
        *TRANSMITTED DATA IS PRESUMED TRUE, AND WHEN ALTERATION IS







Dec 27 21:24 1985  data.tap Page 2


DISCOVERED, ITS READILY BLAMED ON THE EQUIPMENT.
        *THE LAWS CONCERNING TAPS ON UNCLASSIFIED AND NON-FINANCIAL COMPUTER
DATA ARE EITHER QUITE LACKING OR ABJECTLY STUPID.

THE POINT OF ALL THIS IS THAT THE PRUDENT MANAGER REALLY OUGHT TO ENCRYPT
ALL DATA TRANSMISSIONS. ENCRYPTION PACKAGES ARE CHEAP (A 'DES' PROGRAM IS
NOW PRICED AT $30) AND ARE EASY TO USE.

-------------------------------

Editor's Note: This file was aquired by me from a BBS, the is for 'Computer
Security' people only (hehehehe). If you want to fone # just e-mail me. But
please don't crash the board, if is much more valuable up and running where
we can keep an eye on it & THEM.
	-Elric of Imrryr
	Co-Founder of Lunatic Labs
        This file was format for 80 column printing on a UNIX System


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