Walsingham's Pigpen Cipher (1586-1587)

I uploaded a new article about a pigpen cipher used in letters from Thomas Wilkes to Sir Francis Walsingham. See "Walsingham's Pigpen Cipher (1586-1587)"

I wrote the most part of this some weeks ago but I didn't have time to complete it until now.

 

A Numerical Cipher in an Italian Letter to Francis I (1530)

During the sixteenth century, numerical ciphers were not common in France. One letter from London to Francis I (1530) is the earliest French numerical cipher I know, though, as expected, the letter is in Italian.

For a long time, I have been wondering what kind of cipher this is. Now Daniel Bourdeau deciphered it. I uploaded a new article about this, "A Numerical Cipher in a Letter to Francis I (1530)".

 

A Cipher between Louise of Savoy and Nicolas Raince (1525)

Louise of Savoy, mother of Francis I, acted as regent from 1525 to 1526 when the king went to war in Italy and during his captivity in Spain (Wikipedia).

I learned from Ryan Turner that a letter to her (25 October 1525) from Nicolas Raince, secretary of the French ambassador to Rome, in Dupuy 452 used Nicolas Raince's cipher (1526) I reconstructed in "French Ciphers during the Reign of Francis I" and that the letter is printed in Jacqueton (1892), La politique extérieure de Louise de Savoie, XXXIII, pp.366-370 (Internet Archive). He points out that this identification shows that the 1526 cipher had been used as early as 1525 (his github). Although it is now known that cipher was used in France much earlier than this (see my blogpost), the year 1525 is interesting because nonsporadic records in cipher start to appear in 1525.

 

BnF Dupuy 452 includes the following letters partly in cipher, all using the same cipher and printed in Jacqueton (1892):
f.20 Alberto Pio de Carpi to Louise of Savoy, Rome, 22 October 1525, deciphered on f.22
f.24 Nicolas Raince to treasurer Florimond Robertet, Rome, 24 October 1525, deciphered on f.25
f.28 Nicolas Raince to Louise of Savoy, Rome, 25 October 1525, deciphered on f.31

 

Turner also published reading of some letters mentioned in my articles by using the respective keys mentioned:
Gramont's letter from BnF fr.2980 I mentioned in "French Ciphers during the Reign of Francis I" (his github); and
Danzay's letter to the Cardinal oof Lorraine I mentioned in "Danzay's Ciphers: Ciphers of a French Diplomat with a Long Tenure" (his github)

.

Use of Cipher in Cardinal Schiner's Letter to Henry VIII (1516)

The earliest users of cipher in England include Catherine of Aragon, John Stile, Thomas Spinelly, and Cuthbert Tunstall (see "Earliest English Diplomatic Ciphers"). To this may be added Richard Pace (Letters and Papers, Henry VIII, vol.2 (BHO), Wolsey's envoy.

On the receiving side, Brian Tuke is mentioned as the one who deciphered Spinelly's letters to Henry VIII or Wolsey (ibid. (BHO)). The cipher in a letter, dated 14 June 1516, from Matthew Schiner, Cardinal of Sion, to Henry VIII (ibid. (BHO) no.2044-2045) may also have been deciphered by Tuke.

I learned of the latter letter in a write-up by Daniel Bourdeau, who found that the letter is printed with decipherment in A. Büchi (ed.), Korrespondenzen und Akten zur Geschichte des Kardinals Matth. Schiner, vol. II (1516-1527), Basel 1925. It is amazing how his bot searches many sources to find a specific letter in a relevant volume, though it cannot get inside sources with "a bot check".

According to Bourdeau, Büchi tells in the preface that the volume includes 29 letters partly in cipher and names five kinds of cipher used by Schiner and his agents "above all in dealings with England". Inspection of the original materials is desired to see exactly what kind of ciphers were used in these. (At least, the original of some letters by Schiner and Pace are preserved in Cotton MS, Vitellius B XIX.)

It will shed light not only on possible influence on the earliest English ciphers but also on Vatican ciphers at this early stage. One letter addressed to Schiner in 1520 was written as a continuous stream of digits similar to, but much simpler than, later Vatican ciphers (see "An Early Vatican Cipher (1520)"). It would be interesting to know whether schiner's official correspondence used such a simple cipher.

Three Ciphers between Adrian of Utrecht and Charles V (1520-1523)

It has been known that Adrian of Utrecht and Chares V used cipher as early as 1520. When I saw a cipher between them in 1522-1523, after Adrian became Pope, reconstructed by Olga Kolossova (Ko.4) is a typical Spanish cipher, I wondered whether the cipher used in 1520 was so complex as this.

Now, I find that Adrian and Charles used a simple homophonic cipher in 1520 by cryptanalysis by Mikel García Larragan.

Also, the cipher used in October-December 1521 mentioned by Daniel Bourdeau appears to be the same as Ko.4. If so, it indicates that Adrian and Charles V used the same cipher before and after Adrian became Pope in January 1522. Inspection of the original images is desired. (I couldn't locate PTR 2/1/94, 99, 100, and 101 in PARES.)

Daniel Bourdeau also found that a letter jointly sent by Adrian and two other governors of Castile in December 1520 was deciphered in the nineteenth century by Claudio Pérez Gredilla. From his write-up, we see this is a typical Spanish cipher with three-letter code. I suppose Adrian learned this type of code in Spain.

See the new section I added in "Scholarly Studies on Ciphers in the Reign of Emperor Charles V".

Many Telegrams Related to Sun Yat-sen in Japanese Archives Deciphered

A few days after identifying the code condenser to decipher the telegram to Sun Yat-sen (reported the other day), Daniel Bourdeau found that the telegram was only part of a larger collection. He succeeded in deciphering many of them. One is a report of assassination of Chen Qimei (陳其美) sent the day after the event. I wonder whether these telegrams reached the recipient and are preserved for historians. If not, his achievements will shed new light for historians.

Two pieces of news for crypto people. First, Bourdeau found telegrams that cannot be read with the family of code condensers he found combined with the standard character code. I added this in my list of unsolved ciphers.

Secondly, I successfully determined the mapping between the character code and the three-kana code identified by Bourdeau.

See the new section in "Solution of Two Chinese Cipher Telegrams Archived in Japan (1916)".

Solutions of Ciphers in a Continuous Digit Stream

I have been interested in ciphers written in a continuous sequence digits without a break. To solve such ciphers, the first step is parsing the digit stream into cipher units. I uploaded a new article, "Solutions of Ciphers in a Continuous Digit Stream" to describe recent solutions of such ciphers .

Of these, the Soglia cipher solved by Daniel Bourdeau is one for which a reward was offered in 1848.

The Starhemberg cipher solved by by Andrew Aymeloglu employs a fairly complicated scheme, for which he found the key among numerous keys in the DECODE database.

Bishop of Worcester's Latin Cipher with Superscripts Reconstructed from Decipherment in Print

I was told by Andrew Aymeloglu that plaintext of two of the Bishop of Worcester's letters in cipher is printed in publications. When I put them in my list of unsolved ciphers, I thought there was not much to be done to complete the decryption. As it turned out, however, many of the unidentified symbols represent whole words. It would have been hard to identify them from scratch. See "Bishop of Worcester's Latin Cipher with Superscripts (1526, 1529)".

One anonymous letter seems to employ the same cipher but has many yet unidentified symbols, many of which would be nulls or words. I re-marked this as yet unsolved.

Two Diplomatic Ciphers of Marquis de Villars (1669, 1671)

Some letters from Louis XIV to Pierre Villars, Marquis de Villars, are put on auction at Spink (I thank Patrick Hayes for the information). They are interesting in the study of codes and ciphers early in the reign of Louis XIV.

One (1669) seems to use "Colbert-Croissy Cipher (1668-1674) (DE=68) but there still remain many unidentified symbols.

I reconstructed the cipher used in another (1671). As far as I know, it is the only French cipher that had no regularity in arrangement before Louvois' in 1676.

See "Two Diplomatic Ciphers of Marquis de Villars (1669, 1671)".

PS. Patrick Hayes also discovered a letter part of which is in "Cipher with Prince Rupert, Digby, and Ormonde (1644-1645)" ("King Charles I's Ciphers"). The letter is Digby to Prince Rupert, dated 12 July 1644. He provided additional elements:

83=.

87=:

h3=now

Many thanks for the info!

Louvois' Petit Chiffre (1690-1691) Solved

Daniel Bourdeau solved "French Cipher Despatch received by General Catinat (1691)" in my list of "Unsolved Historical Ciphers".

He has been solving so many items in the past few days (he told me he solved 26, with avg 1-2 hours per problem) that I cannot catch up in updating my list. So I put a notice in my list that people about to start working should first check his website. As far as I have seen, his solution and analysis are of very high quality.

For this particular case, automatic codebreaking by AI failed. He found another ciphertext in the same cipher with a paraphrased translation, in which matching ciphertext-plaintext portions could be found from recurring symbols.

See "Solution of Louvois's Petit Chiffre (1690-1691)" and his github quoted therein.

Two Chinese Cipher Telegrams (1916) Solved

Two Chinese cipher telegrams from 1916 presented in "Chinese Cryptography: 1871-1945" are now solved by Daniel Bourdeau.

The one is a telegram to Sun Yat-sen, for which he identified the code condenser (kind of superencryption) by brute force attack after cleverly narrowing down the search scope.

The second was not technically "unsolved" because the decryption is attached, but the encryption scheme has not been known. Bourdeau found it is a three-kana code. It still remains to be found out how the three-kana code groups are mapped to character numbers in a codebook.

See "Solution of Two Chinese Cipher Telegrams Archived in Japan (1916)" and Bourdeau's github pages quoted therein.

 

Solution of a Syllabic Cipher (Le Tellier-Castelnau Cipher, 1657)

An undeciphered letter from Le Tellier to Marquis de Castelnau, dated 12 May 1657, is presented in "Ciphers Early in the Reign of Louis XIV". From other letters in Le Tellier's correspondence at the time, it is considered to be in a syllabic cipher. The ciphertext spanning a little over half a page seemed too short for a conventional solver for general syllable assignment.

To my pleasant surprise, it was solved by Robert Pitt. I guess the regularity of the assignment was given as a constraint or training data. The solution is described in a new short article, "Solution of Le Tellier-Castelnau Cipher (1657)".

Protecting Authenticity of Documents against Breaking of Encryption Scheme by Quantum Computing

IonQ published a blueprint for breaking 256-bit elliptic curve signatures used in blockchain technology including Bitcoin (press release). Unlike prior work, they "compiled every operation down to the actual error-correction primitives our architecture runs. Today's paper proved - rather than assumed - a lower bound on the probability that the full computation succeeds." They estimated that solution of 256-bit ECDLP (elliptic curve discrete logarithm problem, the classically intractable mathematical problem underlying elliptic curve cryptography) on secp256k1 (parameters specifying a specific elliptic curve on which mathematical operations are done) takes 25.7 days per attempt, by using 19397 physical qubits (quantum bits) implementing 1457 logical qubits and 39 million Toffoli gates (means for operating on qubits). (Use of quantum states necessitates complicated error correction schemes, which inflates the number of physical qubits required to implement logical qubits.)

I was reminded of an issue of potentially compromising authenticity of documents by their remark, "The cryptographic exposure this work describes relates to authentication and integrity rather than to confidentiality.... Unlike an attack on encrypted data, a signature compromise is exploitable going forward rather than retroactively against traffic recorded today. "

The threat to confidentiality is already quietly underway through a strategy known as "Harvest Now, Decrypt Later" (my blogpost). On the other hand, breaking of the signature scheme does not allow tampering with a document already signed with the scheme. Instead, it allows an attacker to derive a private key from a public key, which means that the attacker can put an authentic digital signature to a forged document. Suppose there is a digitally signed document stating "The President is very unpopular." Even with the knowledge of the private signature key, the attacker cannot falsify it to read "The President is very popular." Instead, however, it will be possible to create a new document stating "The President is very popular." and put a digital sign to authenticate it.

The same applies for digital timestamping because digital timestamping works by putting a digital signature to a combination of a hash of a document and a timestamp by a trusted timestamping authority to prove that the document was present at the time indicated by the timestamp. If the signature scheme is broken as of 2030, the attacker can create a document stating "The President is very popular." and add to it a valid timestamp of 2026.

Experts are aware of the issue and one (cenceptually) simple solution is timestamp renewal, whereby a document with a timestamp as a whole is wrapped in another layer of digital timestamping with a new (e.g., quantum-resistant) signature scheme. But this renewal need to be done before the original signature scheme is broken.

Wellington's Code/Cipher during the Peninsular War

Some months ago, I wrote about a British book cipher during the American Revolutionary War. This time, I uploaded a new article about Wellington's dictionary code: "Wellington's Polyalphabetic Cipher with a Dictionary Code". For words/names not found in the dictionary, a polyalphabetic cipher with heavy nulls was used.

My observations are based on Wellington's despatch to General Maitland dated 2 September 1812. I thank George Lasry for the information of the auction of the letter at Spink.

Route Transposition Ciphers during the US Civil War Solved by using AI

Two undecoded telegrams to Union General Milroy were solved by Richard Bean, who had Claude Opus 5 solve them. While there are many papers about codebreaking with AI (see my blogpost for some), this is the first case that I see commonly available generic AI solve a real historical cryptogram.

I note the transposition route is the same as that of Stager Cipher No.7 albeit with a different number of lines. I uploaded a new article "Stager Cipher No.7 Continued in Use after Abandonment" about this.