Soviet Diplomatic Code 26 and the elusive Dr Roeder

The Soviet Union used one-time pad to encipher its diplomatic codebooks after 1927. What prompted them to do so? In that year the British government raided the Arcos company that acted as a front for Soviet espionage. The information released by the British government must have convinced the Soviet authorities that their codes were being read (which was true).

From that time on Soviet diplomatic messages used OTP which if used properly is theoretically unbreakable.

During the war however 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 messages sent during the period 1942 -48.

But 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  [Source: ‘’Venona’’ p4 by Nigel West].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…

There are three 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 [Source: JMA/SAC 77 plus others found in HW 40/29]

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 .[Source: Ticom I-205 ‘’Detailed interrogation report of former  Regierungsbaurat  Johannes Anton Marquart of OKH/Gen.d.NA’’

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.