Soviet Diplomatic Code 26 and the elusive Dr Roeder

The Soviet Union used several cryptologic systems in order to protect its communications from the rest of the world. The diplomatic service initially relied on the single transposition cipher and later 3-figure codes also transposed (1). In the early 1920’s a new basic system appeared. Several 2, 3 and 4-figure codes were used, enciphered with large additive tables (1.000 5-figure groups in 100 rows of 10 groups each).

These systems offered limited security and were read by codebreakers in Germany (2) and in Britain (ARCOS case). In 1927 the British authorities raided the Arcos company that acted as a front for Soviet espionage and in the ensuing investigations released information coming from deciphered Soviet telegrams. The compromise of their diplomatic codes led the Soviet authorities to introduce a new enciphering procedure.

From that time on the Soviet diplomatic service used figure codes enciphered with one time pads, a system which if used properly is theoretically unbreakable. Other Soviet agencies operating abroad such as the Trade organization and the intelligence services NKVD and GRU also used codebooks enciphered with one time pads.

However it seems that there were certain errors in the way the system was used and thus some communications were again compromised in the 1940’s.

Several sources claim that during WWII there were problems in printing the large number of random pads and someone decided to reuse those already printed in more than one link . This allowed the Americans to solve some Soviet intelligence service messages sent during the period 1942 -48. This program was called VENONA and it uncovered many high placed spies inside the US and Britain.

If the Anglo-Americans could read some Soviet communications enciphered with one time pad, could other countries have done the same? What about the Germans ? Did they have any success with Soviet diplomatic codes?

Let's take a look at the European Axis Signal Intelligence volumes :

From EASI vol6 - The Foreign Office cryptanalytic section  , p31
 
y. Russia. Work on Russian diplomatic systems does not seem to have been a Pers Z S commitment. Dr. Kunze made it clear that Russian systems had been read up until 1927, but that no success had been achieved after that time. Presumptively he had reference to the introduction of one-time pads. Lt. Colonel Mettig of Signal Intelligence Agency of the Supreme Command Armed Forces (OKW/Chi) stated that "after a certain date" (which he could not remember), no Russian diplomatic traffic was attempted, either by his agency or Pers Z S.
This paragraph creates more questions. If the Pers Z did not work on Soviet diplomatic traffic who did ? The only other organizations that tackled diplomatic traffic were OKW/Chi and the Forschungsamt.   


From EASI vol7 -  Goering’s Research Bureau , p84

Russian Systems.

Diplomatic Code and Additive.

Sauerbier mentions a few  people who were engaged in a fruitless attack on Russian diplomatic traffic. This attack culminated in the belief that the system was a code with a non-repeating additive. (I-162.)

From EASI vol3 -  Intelligence Agency of the Supreme Command Armed Forces , p63

f. Russia. The Russian desk was under Professor Nowopaschenny. Wendland, the head of the practical cryptanalysis section, (Section V) was also interested in Russian. It is known that, as early as 1934, Nowopaschenny was connected with the Cipher Section, and was interested at that early date In Russian problems. At that time, Russian military traffic was being worked on. During the war, the Russian section was small, and it seems to have been able to accomplish nothing. Mettig stated definitely that Russian diplomatic traffic was enciphered with a one-time pad and was never read. Traffic was intercepted from time to time and tested, but the desk never had any luck.The Foreign Office People said that up to the time of Stalingrad the Army read a Russian diplomatic system based on a one-time pad.They were probably mistaken. The system read vas almost certainly a military system. We know that such a system was read. A diplomatic system would not have been handled by the Army.

The military one-time pad read in 1942 was of course the 5-figure code used by the Soviet High Command and not a diplomatic system.

If the Germans had no success with Soviet diplomatic codes during the war how can we explain the following message by Oliver Kirby :

[Source: Robert Louis Benson and Cecil J. Phillips, History of Venona (Ft. George G. Meade: Center for Cryptologic History, 1995)]

The diplomatic code 26 was one of the codebooks captured by the Finns at the Soviet Consulate at Petsamo on 22 June 1941.The other books were the NKVD Pobeda code , a GRU codebook and a Naval GRU codebook (3).These were shared with the Germans and Japanese.

Strangely there is no mention of these books in the European Axis Signals Intelligence volumes. In volume 8 p77 two Russian systems are mentioned as being  physically compromised ,during the war, but no further details are given…

I’ve tried to find information on dr Roeder but I have been unable to locate any person by that name working at Pers Z. Another possibility is that Roeder worked for another German agency. There was a Roeder, head of group VI of OKH/GdNA but in his interrogation it is mentioned that he was captured by Allied troops in the South of Germany. Kirby was in the North.

Were the Germans able to read Soviet diplomatic messages? Cryptologia article ‘’The road to German Diplomatic ciphers’’ by Michael van der Meulen mentions that Paschke of the Pers Z in his memoirs clearly states that Soviet diplomatic messages were read. The book in question is  ‘’ Das Chiffrier und Fernmeldewesen im Auswärtigen Amt’’,Bonn-1957.

According to EASI vol6 ‘’While junior in grade to Schauffler, Dr.Paschke during the latter years of the war became, with Schauffler, the joint head of Pers Z S. So he should know…

Dr Adolf Paschke worked in the Foreign Ministry's deciphering department Pers Z and was head of the linguistic cryptanalysis group. In the recently declassified TICOM report DF-111 ‘Comments on various cryptologic matters’ he says that Soviet diplomatic communications were indeed solved in the period 1927-1930 since the Soviets used each additive page twice (4).

From 1930 the system was changed and the pads were no longer reused. However Paschke had identified the use of the same tables more than once in the same circuits and he believed that if the entire traffic of different organizations (diplomatic and NKVD) was examined more of these repetitions would be uncovered (5).

Regarding solution of the current Soviet OTP system he did not mention any success but cryptically stated that Russian material of the Forschungsamt and the High Command’s deciphering department OKW/Chi were destroyed during the war (6).

Could the Germans have solved any messages during the war? There are three theoretical possibilities on how they could have done so :

1).The one-time tables were reused. This was the basis of the American Venona breakthrough. The Germans were able to read Soviet military messages enciphered with one-time pad thanks to reuse of the tables. Perhaps they did something similar with diplomatic traffic.

2).The success was achieved not against the one-time pad but against the emergency enciphering procedure. This was a simpler way to encipher messages when there was no supply of OTP. The Japanese read messages on this system from embassies/consulates in Seoul, Dairen, Australia, Harbin, Hakodate (7).

3).They were able to reconstruct the one-time pad algorithm. The Anglo-Americans were able to discover the algorithm used by the German Foreign Ministry in creating their ‘’random’’ additive tables in late ’44 and messages were decoded in 1945. Did the Germans have similar success? A major effort to identify the OTP algorithm was carried out during the war by the Army’s Signal intelligence agency but it yielded no results (8).

I believe that there is more to this story than has been presented so far. Unfortunately we are at the mercy of the NSA and GCHQ .If/when they release new material then we will know more.

Notes:

(1). TICOM DF-111, p4-5

(2). TICOM DF-111, p6

(3). ‘Venona’ p4 by Nigel West

(4). DF-111, p7

(5). DF-111, p12-15

(6). DF-111, p18

(7). JMA/SAC 77 plus others found in British archives HW 40/29

(8). Ticom I-205 ‘Detailed interrogation report of former Regierungsbaurat Johannes Anton Marquart of OKH/Gen.d.NA’