Although the Poles were successful in the offence they neglected their defence.Their diplomatic ,military attaché and resistance movement codes were read by the Germans during the war.
The information concerning the codes of the Polish resistance movement comes from ''European Axis Signal Intelligence in World War II '' :
EASI vol4 -Army High Command Signal Intelligence Service p179,180
Work on Polish Resistance Movement traffic - The most notable results in the Agents section were achieved in the interception and solution of the systems used by the Polish Resistance Movement, particularly during the Polish uprising in Warsaw in 1944.From information passed on this system, the dispositions of the Polish liberation troops as well as friction between them and the Russians could be established. It was possible, moreover, to solve all wireless traffic which the Polish government in London carried on with its organizations in Poland. In, order to preserve secrecy and to insure quicker delivery of the decodes, eight members of the Vauck section were transferred in the autumn of 1943 to the Polish section of the Signal Intelligence Agency of the Supreme Command, Armed Forces (OKW/Chi) for work there. The clear text was published by the Armed Forces in their bulletins and was given extremely restricted distribution, To insure complete radio intercept coverage, the Armed Forces Agency (OKW/Chi) ordered its station at Lauf also to intercept the traffic. First Lt. Schubert, a cryptanalyst of GdNA, wrote a brief account of the systems used by the Polish National Resistance Movement in which he stated that systems 006, 117, 118, and 181 were broken and that others were worked on. Most of them were simple two figure substitutions used without an indicator, with some variations in development and the use of basic keys or key phrases.
EASI vol 3 – Signal Intelligence Agency of the Supreme Command Armed Forces p58
The most valuable intelligence results from Polish traffic, however, were obtained through the breaking of the traffic between the underground organization in Poland and its government in London. This traffic was said to have been particularly valuable during the period immediately preceding the Normandy Invasion. All wireless traffic from England was banned, but the traffic of Polish agents to England continued and was read. Most of this traffic seems to have been in a five-figure system. The original break was apparently made not by OKW/Chi but by the Agents Section of Inspectorate 7/VI (In 7/VI).Once the break had been made, however, the traffic proved to be so valuable that in the autumn of 1943 a group from the Agents Section of In 7/VI was transferred to the Polish desk of OKW/ Chi where it worked as part of the organization. The translated clear texts were published as regular VN’s and given an extremely limited distribution. The traffic itself was intercepted by the OKW/Chi intercept station at Lauf.
The Brits found out about the German success with Polish codes by intercepting and decrypting German messages in September '44.It’s not clear what measures were taken to close off this leak .
Here are some intercepted messages from British Archives HW 40/244 ‘’Polish: evidence that the OKW (High Command of the German Armed Forces) was reading traffic passing between London and the Polish underground’’ :
Secret. To Chief of Security Police in the General Gouvernment, Dept.(roman) IV, for Ostubaf. SCHINDHEIM, CRACOW. (Dated 30/8).
Subject: 6207 from LONDON to WARSAW, 23/8/44, no address, No. 500, No. 199 Text A point 3.
The government is negotiating for an agreement with the Soviet Government with a view to a common prosecution of the war against the Germans. These agreement proceedings should lead to a lasting Polish-Soviet friendship after the war., This rapprochement should offer possibilities of a Polish-Soviet alliance which should guarantee close political and economic cooperation between Poles and the Soviets while recognizing the principles of the sovereignty of each state and the obligation of non-intervention in the internal affairs of the other country. Aim of the alliance will also be envisaged as the elimination of German influences in Central Europe and preventing the possibility of a repetition of German aggression. Further alliances between POLAND and GREAT BRITAIN and FRANCE will serve this purpose. Another alliance will be formed with CZECHO- SLOVAKIA. In similar manner the most friendly relations with the U.S.A. will be cultivated.POLAND will share the rights which will ensure peace to the Peoples striving for peace by a general security system. POLAND will also participate in the occupation of GERMANY, principally in those eastern territories which will abut on the future Polish frontiers .In the settlement of POLAND’s frontier problem the Polish Government will be guided by the following principles which have been brought into uniformity with those of the SOVIET UNION in a spirit of friendship and with regard to the basic interests of the Polish nation. 1) POLAND, which has sacrificed so much in this war and which alone of all the nations occupied by GERMANY produced no QUISLING, cannot emerge from this war territorially diminished. In POLAND the main centres of cultural life in the East and the sources of raw material which are necessary to a guarantee of the economic life of the Polish State will remain. A new ruling on questions of nationality, restoration of citizenship arid voluntary exchange amongst the POLISH, UKRAINIAN and WHITE RUSSIAN populations will be undertaken. The ultimate settlement of the question of the POLISH-SOVIET frontier will be decided in conformity with the requirements of democracy by the constitutional parliament £SEJM£. In the North and the West no removal of the German population will (remainder not seen).
From OKW WNV Fu. (Roman) III J (0), No. 2262/44, on 30/8:-
From WARSAW to LONDON, 25/8/44, to Colonel PERKINS, No. 651, 25/8,
JULIUS ,WARD No. 54293. Subject: RAF.
"Dear Sir, help is urgently necessary in the centre of the city of WARSAW. Ammunition for the anti-tank weapon of the PIAT type which was sent is completely exhausted. Dear Sir, the most important (word illegible) needed are (word illegible), anti-tank weapons, heavy machine-guns, ammunition of all kinds. The best area for dropping is the area south of the JEROZILIMSKA Avenue in its continuation to the East as far as NOWY SWIAT, West as far as the MARSZALKOWSKA and south as far as PIUSA Street. This area is free from Germans. Dear Sir, I received your communication of 19/8/44 on 20/8/44. Signed JULIUS WARD."
In subsequent posts i'll look into the compromise of Polish diplomatic and military attache codes.