24 December 2002
These two reports describe TEMPEST deficiencies in a US Army Signal Battalion facility. Note the differences between the two reports, dated 10 months apart, for technical security scope and types of threats examined. The first addresses telephonic, audio, audio vibration, and transmission line leaks and clandestine devices, while the second covers those of the first as well as electronic, radio frequency and building element transmission leaks. This latter scope is closer to what is publicly known of current technical security and TEMPEST countermeasures. The US Army regulation cited below, AR 381-14, Technical Surveillance Countermeasures (TSCM), remains classified Secret.
In response to a 1999 FOIA request the National Security Agency released to Cryptome several declassifed TEMPEST documents:
Another report from this dossier on TEMPEST leaks: http://cryptome.org/tempest-leaks.htm
Another dossier in the released INSCOM material describes the investigation of a passive acoustic cavity resonator found in a military facility which had been unrecognized by users of the facility for several years. Most personnel inteviewed who recalled the object thought it was a discarded machine part of no signficance. The device's origin was never determined.
Surreptitious cavity resonators are passive and emit no identifying signals. They are shaped to acquire and reflect electromagnetic emanations of equipment, either constantly or when "illuminated" by a receiving device. They are customarily camouflaged as innocuous objects or concealed within unsuspicious objects.
A cavity resonator discovered in the Seal of the US Embassy in Moscow, a gift of the Soviets, was planted to listen and transmit data when "illuminated" by its operators. The book Spycatcher describes cavity resonators planted by the United Kingdom in several communications facilties of allies and foes.
Source: FOIA material received from the US Army Intelligence and Security Command, November 25, 2002. Excerpted from Dossier ZG000495W, Corps Communication Center, pages 31-41.
DOWNGRADED AT 12 YEAR INTERVALS NOT AUTOMATICALLY DECLASSIFIED DOD DIR 5200.10 REGRADED UNCLASSIFIED ON MAR 18 1998 BU CDR USAINSCOM FOIPO Auth Para 1603 DoD5200 1-R
CONFIDENTIALDEPARTMENT OF THE ARMY STUTTGART STATION 766TH MILITARY INTELLIGENCE DETACHMENT 66TH MILITARY INTELLIGENCE GROUP APO 09154 AEUTMI-O-Q(I&S) 13 MARCH 1970 SUBJECT: Counterintelligence Technical Security Inspection (U) Commanding Officer 34th Signal Battalion APO 09154 1. (U) INTRODUCTION: On 10 March 1970, a Coungterintelligence Technical Security Inspection of the following elements of Headquarters, 34th Signal Battalion, APO 09154, located in Building 1601, Krabbenlock Kaserne, Ludwigsburg, Federal Republic of Germany, was conducted by Special Agents [------redacted------] and [-----redacted-----] Stuttgart Station, 766th Military Intelligence Detachment: a. Office of the Commanding Officer b. Office of the Executive Officer c. Office of the Battalion Adjutant d. Office of the S2 e. Office of the S3 A floor plan of the inspected area is attached as EXHIBIT I. The inspection was conducted to detect the presence of technical surveillance equipment and to determine the existence of hazards to technical security which would permit the employment of such equipment, and to recommend technical security measures designed to prevent successful employment of technical surveillance equipment. 2. ( C)U LIMITATIONS: Counterintelligence Technical Security Inspections of the type conducted indicate the security status of the inspected area at the conclusion of the inspection within the capabilities of equipment and operational techniques employed. Admission to the inspected area of unauthorized persons or personnel not having proper security clearances, who are not under the escort of reliable personnel; failure to maintain continuous and effective surveillance and control of the inspected area; allowing repairs or alterations to or within the inspected area without the supervision of qualified and responsible personnel; or the introduction of new furnishings into the inspected area prior to the completion of a thorough inspection of such furnishings, will nullify the security afforded by this inspection. 3. ( C)U FINDINGS: a. The inspection did not locate or indicate the presence of surreptitious technical surveillance devices. b. The inspected area is not considered secure for classified confer- ences or discussions until corrective action has been accomplished relative to the following hazards to technical security: (1) Located as listed below are Western Electric Company Model 500 telephone instruments: (a) Office of the Commanding Officer, one. (b) Office of the Battalion Adjutant, one. (c) Office of the S2, one. (d) Office of the S3, five. Although the Western Electric Model 500 telephone instrument is considered the most secure for general use, the instrument is vulnerable to alteration and modification by personnel involved in the installation and maintenance of the instrument. The modification of a telepone instrument to establish an extremely effective listening device requires only a few seconds and is impossible to detect except by qualified personnel equipped with appropriate countermeasures equipment. (2) Located as listed below are standard US Army field telephone instruments: (a) Office of the Commanding Officer, one. (b) Office of the S3, one. Examination of the instruments revealed that all instruments were functioning properly; however, frequent use of a field telephone instrument often results in the retainer switch becoming too weak to hold the handset in the proper position to cause the line switch to be activated to block audio. When such a condition exists, one hundred percent audio from the room in which the defective instrument is located is passed over the length of the telephone transmission lines. The audio passed may be taken from any point along the trasnmission line by attaching a small, commercial, inexpensive amplified to the line. Field telephone instruments constitute a constant severe hazard to technical security even when the handset retainer switches function properly, as many users are not aware that the handset must be placed in the cradle firmly to activate the line switch. Additionally, it is a common misperception that the "push to talk" switch must be depressed for audio to be passed over the line. The "push to talk" switch only activates a noise cancelling element of the instrument to aid the person listening during the conversation. It does not block audio from passing over the line via the receiver portion of the handset. (3) Located within the Office of the Executive Officer is a multi- line telephone instrument, Model STE 120/29, constructed by Telefonbau and Normalzeit, a German electronics firm. Although a visual and limited electronic inspection of the instrument was conducted, a thorough electronic inspection, for the purpose of detecting the more sophisticated clandestine listening devices, cannot be conducted with the equipment currently available to United States Intelligence. A photograph of the instrument is attached as EXHIBIT II. (4) Located within the Office of the Commanding Officer is an Intercom Station, Model LS 127/F1, manufactured by Webster Electric Company, which extends to a variety of speakers which serve as slave stations for the above mentioned master station. A photograph of one of the above mentioned slave station speakers, located in the Office of the S3, is attached as EXHIBIT III. The sub-stations, all of which are of the open monitor variety, were found to pass one hundred percent audio from the rooms in which they were located, even though the sub-station was not activated. Additionally, the entire intercom system utilized existing telephone lines thus causing a situation wherein each classified conversation conducted within a room containing a sub-station is passed over uncontrolled transmission lines in the clear. The audio passed may be obtained from any point along the transmission lines by attaching a small, inexpensive, commercial amplifier to the transmission lines, outside of the the headquarters building. (5) The inspected area, located on the ground floor level, is vulnerable to attack by clandestine listening devices. The placement of a very effective listening device against the windows or window frames poses no problem to a hostile intelligence agent as the outside of the building is afforded no protection. 4. ( C)U RECOMMENDATIONS: In view of the findings, the following recommenda- tions are made for the improvement of counterintelligence technical security: a. Reference paragraph 3b(1), above: It is recommended that each telephone instrument be equipped with a plug and jack disconnect device situated in a position convenient for use and that the instruments remain disconnected from the lines at all times the instrument is not in use. It will be necessary to install a separate ringer for each telephone number to alert office personnel to an incoming telephone call. It is recommended that Western Electric Model R1A or ERickson Model KLG 5103-2 ringers be installed and that the ringers within each telephone instrument be discon- nected and removed. Paragraph 10b(3), AR 381-14, requires all telephone instruments located in Secondary Sensitive Areas to be equipped with a disconnect device. b. Reference paragraph 3b(2), above: It is recommended that the instrument be disconnected from the line at all times except when required by operational activities. It is further recommended that all personnel using the instrument be instructed that the handset must be replace properly in the cradle after each use. c. Reference paragraph 3b(3), above: It is recommended that the instrument be replaced with Western Electric Company Model 565 multi-line telephone instrument. In the event that such equipment is not available, it is recommended that the present telephone instrument be equipped with disconnect devices and the the instrument be disconnected from the line during periods of classified and/or sensitive conversations withing the room. d. Reference paragraph 3b(4), above: It is recommended that the intercom system be removed. In the event operational necessity dictates the retention of the system, it is recommended tha appropriate assigned personnel be made aware of the fact that all conversations conducted within the rooms in which the sub-stations are located are being passed over un- controlled telephone lines. The passing of audio by sub-stations is inherent in intercom systems and constitutes a constant severe hazard to technical security. While some commercial firms manufacture intercom systems with built-in safeguards to prevent passing of audio when the system is not activated, the expense of the instruments precludes their use. e. Reference paragraph 3b(5), above: It is recommended that an appropriate responsible individual be appointed to periodically inspect the outside walls of the inspected area to detect placement of attachments, wiring, etc., and to determine ther reason for placement of such items. f. It is further recommended that the hazards to technical security outline above be included in the initial security briefing of newly assigned personnel, as appropriate, and that the hazards be made a point of emphasis in subsequent scheduled security briefings. 5. (U) EXIT BRIEFING: Major Bobby R. Harris, S2/3 Officer, was informed of the findings and recommendations stated above at the conclusion of the Counterintelligence Technical Security Inspection. THOMAS C. WILKINSON II MAJOR, MI Commanding Copies Furnished: Commander-in-Chief United States Army, Europe ATTN: AEAGB-CI(GS) APO 09403 Commanding General VII US Army Corps ATTN: AETSGB-CI APO 09107 Commanding Officer 66th Military Intelligence Group ATTN: AEUTMI-OP-I&S(CI) APO 09108 [Exhibits I, II, and III, 6 pages, omitted here.]
Source: FOIA material received from the US Army Intelligence and Security Command, November 25, 2002. Excerpted from Dossier ZG000495W, Corps Communication Center, pages 275-280.
DOWNGRADED AT 12 YEAR INTERVALS NOT AUTOMATICALLY DECLASSIFIED DOD DIR 5200.10 REGRADED UNCLASSIFIED ON MAR 20 1998 BU CDR USAINSCOM FOIPO Auth Para 1603 DoD5200 1-R
CONFIDENTIALDEPARTMENT OF THE ARMY STUTTGART STATION 66TH MILITARY INTELLIGENCE GROUP APO 09154 REPORT OF COUNTERINTELLIGENCE TECHNICAL SERVICE OF 34TH SIGNAL BATTALION APO 09107 AEUTMI-O-Q(I&S) JAN 14 1971 Commanding Officer, 34th Signal Battalion, APO 09154 Commanding Officer, VII US Corps, ATTN: AETSGB-CI, APO 09107 Commander-in-Chief, USAREUR and Seventh Army, ATTN: AEAGB- CI(GS), APO New York 09403 Commanding Officer, 66th Military Intelligence Group, ATTN: AEUTMI-OA-CE, APO New York 09108 Section 1. INTRODUCTION 1. (U) A counterintelligence technical inspection was conducted during the period of 10 and 11 December 1970 by the following representatives of Stuttgart Station, 66th Military Intelligence Group, APO New York 09154: [Redacted] Special Agent [Redacted] Special Agent [Redacted] Special Agent 2. (U) The Communication Center, 34th Signal Battalion was considered by the requestor to be a secondary, sensitive are in accordance with AR 381-14 (Clas). 3. (U) An examination of records regarding previous counterintelligence technical services in the area revealed that a previous counterintelligence tech- nical inspection was completed on 20 February 1970 by members of Suttgart Station, 66th MI Group. 4. ( C)U a. Unless otherwise indicated, this service was conducted to detect the presence of technical surveillance equipment; to determine the existence of technical security hazards which would permit the em- ployment of such equipment; and to recommend technical security sur- veillance monitoring systems. b. This service consisted of selected application of comprehensive visual, physical, audio, electronic, and radio frequency checks and include an examination of the factors checked below: (1) All exterior building surfaces, utility poles, wires, and other associated paraphernalia. (2) Vulnerability to hostile visual surveillance. (3) All areas adjacent to the serviced area including those area above and below. (4) The interior room areas to include the wall, floor, and ceil- ing mounted items, furniture, artifacts, and equipment. (5) The interior and exterior surfaces and internal structure of walls, floors, ceilings, and other structural objects. (6) All electric and electronic equipment or circuits and compo- nent parts of accessories thereof, to include detailed examination of all wiring and utility channels recesses. [Section II not used.] Section III. LIMITATIONS 5. (u) Counterintelligence technical services of the type conducted indicate the technical security status of the area or equipment examined at the conclusion of the examination, within the capabilities of the equipment utilized and the operational techniques emploued. Attention is invited to the fact that the security afforded by this service WILL BE IMMEDIATELY NULLIFIED BY: a. Admission to the serviced area of persons who do not have the proper security clearance or who are not under proper support. b. Failure to maintain continuous and effective surveillance and control of the serviced area. c. Allowing repairs or alterations to or within the serviced area without the supervision of qualified and responsible personnel. d. The introduction of new furnisings or equipment into the serviced area prior to a thorough examination of such items. Section IV. FINDINGS AND RECOMMENDATIONS 6. (U) Repeated or uncorrected findings: None. 7. ( C)U a. The service did not locate or indicate the presence of tech- nical surveillance devices. b. The serviced area does not meet the criteria for a secondary sensitive area as defined in AR 381-14 (Clas) and is not considered secure for the discussion of sensitive classified information until corrective action is taken on the following technical security hazards: (1) Finding: The electrical wiring within the inspected area was not strictly limited to the established lighting system and electronic devices considered essential to the operation of the sensitive area. (AR 381-14 (Clas), para 10.b.(3)) Recommendation: All excess wiring should be removed. The electrical wiring in the inspected area should be limited as indicated above. (2) Finding: The door of the inspected area is passing audio and audio vibrations from the inspected area. (AR 381-14 (Clas), para 10.b.(1)) Recommendation: The interior of the door should be covered with a sound proofing material, such as acoustical tile, or sound proof- ing drapes. The door between the operations office and the hall door should be closed at all times. (3) Finding: The pipes in the following areas are passing audio vibrations from the inspected areas: (AR 381-14 (Clas), para 10.b.(2)) a. Main Telethype Room b. Rack Room 26 c. Room 29 Recommendation: The pipes should be covered with sound absorbant material from their point of entrance to their point of exit and secured at the inner wall openings to minimize acoustical leakage. (4) Finding: The air condition exhaust duct located on the south wall of the Operations Office is passing audio and audio vibrations from the inspected area when the exhaust motor is not operating. (AR 381-14 (Clas), para 10.b.(2)) Recommendation: A cabinet of sound absorbent material with a series of internal baffles, or a baffled cabinet with soung ab- sorbant material attached to the outside should be constructed around the exhaust motor. (5) Finding: Two Western Electric Company Telephones, Model 500 which are located in the operations office are connected to a ten terminal connector block. These telephones are not equipped with De- partment of the ARmy approved disconnect systems. (AR 381-14 (Clas), para 10.b.(3)) Recommendation: All telephones in the inspected area should be equipped with a Department of the Army approved disconnect system, to include plugs, jacks, and separate ringers. The ten connector terminal block should be replaced with a single T 41 block that will accommodate the two lines that are used in the facility. (6) Finding: The fifteen inch fan in Room 29 with 2 feet of duct leading to the exterior of the building is passing audio and audio vibrations from the inspected area. Recommendation: A cabinet of sound absorbant material with a seris of internal baffles should be constructed around the in- tgerior opening of the duct. Sound absorbant baffles should be con- structed within the duct. Ducts with internal measurements greater tha eight by ten inches should be secured by metal grates permanently affixed withing the duct at a maximum distance from the inspected area and such a location that they may be readily inspected for evidence of unauthorized tampering. (7) Finding: The heating duct which runs from Room 29 to the unrestricted hallway is passing audio and audio vibrations from the in- spected area. (AR 381-14 (Clas), para 10.b.(2)) Recommendation: This duct should be wrapped with a sound absorbant material from the point of entrance to its point of exit. (8) Finding: The air conditioning duct which runs from the main teletype room to the exterior of the building is passing audio and audio vibrations from the inspected area. (AR 381-14 (Clas), para 10.b.(2)) Recommendation: This duct should be wrapped with a sound absorbant material from the point of entrance to its point of exit. (9) Finding: The ductway which extends from the Communica- tions Center to the storage closet on the first floor is passing audio and audio vibrations from the inspected area. Recommendation: The door to this closet should be secured with a Sargent & Greenleaf Combination Padlock at all times to preclude anyone using the area to gain information from the inspected area. The combination to this door should be maintained by the Signal Officer or his designated representative. 8. The Commanding Officer is reminded that paragraph 12e, USAEUR Regualtion 380-5, dated 12 March 1970, requires that this re- port be indorsed through command channels to CINCYSAEUR, ATTN: AEAGB-CI(GS), APO New York 09403, with a listing of corrective action and/or Commander comments for each recommendation made in this report. Section VI. EXIT BRIEFING 9. (U) All findings, recommendations, and limitations of service were discussed during an exit briefing on 11 December 1970 for the following unit representatives: TRAINER Leonard L., Major Ass't VII Corps Signal Officer KECK Michael A., 1LT VII Corps Commo Center Officer GILLIKIN John M., 2LT 34th Signal BN Plt Ldr BETSINGER Gary W. Commo Center CIC [Signature] DAVID C. UNGERER MAJ, MI Commanding Tp: Stgt Mil (2721) 8357/JEW/mm