A developer writing as 'Prinz' reported (Sept 17, 2026) that OpenAI's GPT-6 Astra decrypted a previously unsolved November 1918 ADFGVX German radio message — a 170-symbol transmission about British naval movements near Sevastopol — using the keyword TRUPPENVERSCHIEBUNG, a key already documented in J. Rives Childs's manuscript on German military ciphers, so the key was supplied rather than recovered. The plaintext describes an English cruiser at Sevastopol and an Allied squadron arriving on the 26th; per Prinz (echoed by Tom's Hardware and others), the cruiser date aligns with HMS Canterbury's logs, though the plaintext reads '?4th' and the key's documented start date (December 9) conflicts with the November 27 transmission date. Coverage widely amplified the result, but it remains single-source: no independent cryptographic reproduction or archival verification appears in the supplied material, and the sibling Enigma story (Leffen/the-decoder) is likewise human-scaffolded with documented keys and published materials. Snippets confirm the claim's spread and its bounded shape (known key, known procedure, model-as-executor), but they do not establish 'previously unsolved' status or the naval-records agreement independently.
This is the position Scott already holds: a single-source frontier capability claim can only be defended at the evidence class of its weakest support, and press amplification of one developer's report is an echo, not verification — held in Evidence Class Ladder, Witness Not Oracle, and Mechanically Different Verifiers. Nothing new has arrived on either side since the 9/24 read: no independent reproduction, no archival confirmation, no inspectable step-by-step cipher procedure; the Schneier echo and the Enigma sibling's human-scaffolded correction both reinforce rather than extend the lesson. It would only become actionable (a falsifiable-case-study publishing opportunity) if Klausis Krypto Kolumne–style cryptanalysis replication or HMS Canterbury archival checking landed, and none has.
ip:concept.evidence-class-ladderip:source.witness-not-oracle-ebookip:concept.mechanically-different-verifiersip:concept.correlated-checkers-pitfallradar:concept.claim-verificationradar:anthropic-cryptanalysis-capabilityradar:concept.reproducibility
queries asked of Scott's wikis
- witness not oracle — inspectable evidence for claimed model discoveries
- mechanically different verifiers — checking model output against independent sources
- agent research workflows — model executing a known procedure vs originating a result
- evaluating frontier capability claims — single-source demos and press amplification patterns
- LLM tool-scaffolded tasks — cryptanalysis, solvers, and human-written tooling
- publishing angle — bounded falsifiable claims as case studies in verification discipline
| source | object | author | score | comments |
|---|
| 🟠 reddit | ChatGPT-6 Astra cracks 108-year-old unsolved WWI German code for the first time singularity Retrieved article excerptOpen article · Retrieved 2026-09-19T21:22:41.806100+00:00 # ChatGPT-6 Astra cracks 108-year-old unsolved WWI German code for the first time — radio message sharing enemy movement intelligence had evaded decoding, 1918 Crimean fleet warning verified against HMS Canterbury logs
[News](https://www.tomshardware.com/news)
By
[Mark Tyson](https://www.tomshardware.com/author/mark-tyson)
Published
19 September 2026
The decoded and message alerts German military forces of the movements of an English cruiser and an Allied squadron near Crimea.
When you purchase through links on our site, we may earn an affiliate commission. [Here’s how it works](https://www.tomshardware.com/reviews/about-us,4260.html#section-affiliate-advertising-disclosure).
An 'unsolved' encrypted World War I radio message
(Image credit: [scienceblogs.de](https://scienceblogs.de/klausis-krypto-kolumne/unsolved-adfxvx-messages-from-world-war-i/))
- Copy link
- [Facebook](https://www.facebook.com/sharer/sharer.php?u=https%3A%2F%2Fwww.tomshardware.com%2Ftech-industry%2Fartificial-intelligence%2Fchatgpt-6-astra-cracks-108-year-old-unsolved-wwi-german-code-for-the-first-time-radio-message-sharing-enemy-movement-intelligence-had-evaded-decoding-1918-crimean-fleet-warning-verified-against-hms-canterbury-logs)
- [X](https://twitter.com/intent/tweet?text=ChatGPT-6+Astra+cracks+108-year-old+unsolved+WWI+German+code+for+the+first+time+%E2%80%94+radio+message+sharing+enemy+movement+intelligence+had+evaded+decoding%2C+1918+Crimean+fleet+warning+verified+against+HMS+Canterbury+logs&url=https%3A%2F%2Fwww.tomshardware.com%2Ftech-industry%2Fartificial-intelligence%2Fchatgpt-6-astra-cracks-108-year-old-unsolved-wwi-german-code-for-the-first-time-radio-message-sharing-enemy-movement-intelligence-had-evaded-decoding-1918-crimean-fleet-warning-verified-against-hms-canterbury-logs)
- Whatsapp
- [Reddit](https://www.reddit.com/submit?url=https%3A%2F%2Fwww.tomshardware.com%2Ftech-industry%2Fartificial-intelligence%2Fchatgpt-6-astra-cracks-108-year-old-unsolved-wwi-german-code-for-the-first-time-radio-message-sharing-enemy-movement-intelligence-had-evaded-decoding-1918-crimean-fleet-warning-verified-against-hms-canterbury-logs&title=ChatGPT-6+Astra+cracks+108-year-old+unsolved+WWI+German+code+for+the+first+time+%E2%80%94+radio+message+sharing+enemy+movement+intelligence+had+evaded+decoding%2C+1918+Crimean+fleet+warning+verified+against+HMS+Canterbury+logs)
- [Pinterest](https://pinterest.com/pin/create/button/?url=https%3A%2F%2Fwww.tomshardware.com%2Ftech-industry%2Fartificial-intelligence%2Fchatgpt-6-astra-cracks-108-year-old-unsolved-wwi-german-code-for-the-first-time-radio-message-sharing-enemy-movement-intelligence-had-evaded-decoding-1918-crimean-fleet-warning-verified-against-hms-canterbury-logs&media=https%3A%2F%2Fcdn.mos.cms.futurecdn.net%2FG8KRG6QGgSMerE4dScxCJ9.jpg)
- [Flipboard](https://share.flipboard.com/bookmarklet/popout?title=ChatGPT-6+Astra+cracks+108-year-old+unsolved+WWI+German+code+for+the+first+time+%E2%80%94+radio+message+sharing+enemy+movement+intelligence+had+evaded+decoding%2C+1918+Crimean+fleet+warning+verified+against+HMS+Canterbury+logs&url=https%3A%2F%2Fwww.tomshardware.com%2Ftech-industry%2Fartificial-intelligence%2Fchatgpt-6-astra-cracks-108-year-old-unsolved-wwi-german-code-for-the-first-time-radio-message-sharing-enemy-movement-intelligence-had-evaded-decoding-1918-crimean-fleet-warning-verified-against-hms-canterbury-logs)
- Email
Share this article
[4](https://www.tomshardware.com/tech-industry/artificial-intelligence/chatgpt-6-astra-cracks-108-year-old-unsolved-wwi-german-code-for-the-first-time-radio-message-sharing-enemy-movement-intelligence-had-evaded-decoding-1918-crimean-fleet-warning-verified-against-hms-canterbury-logs#xenforo-comments-3900589)
Join the conversation
[Follow us](https://google.com/preferences/source?q=tomshardware.com)
Add us as a preferred source on Google
Newsletter
Subscribe to our newsletter
Now 108 years after its transmission, an encrypted World War I German radio message has apparently been deciphered for the first time. The decoded and translated message relays information about the movements of an English cruiser and an Allied squadron near the Crimean Peninsula. Prinz, the developer who reckons they successfully decoded this covert WWI communication, used [GPT-Astra](https://www.tomshardware.com/tech-industry/artificial-intelligence/openai-claims-gpt-6-astra-is-an-ethereal-alien-mind-with-agi-like-qualities-company-warns-of-alignment-challenges-as-new-frontier-leader-emerges) to solve the cipher.
Go deeper with TH Premium: AI shortages
Nvidia
(Image credit: Nvidia)
- [AI data centers are swallowing the world's memory and storage supply](https://www.tomshardware.com/pc-components/storage/perfect-storm-of-demand-and-supply-driving-up-storage-costs?utm_source=edit-links&utm_medium=boxout&utm_term=ai-shortage)
- [Demand for data center CPUs has surged, and AI agents are responsible](https://www.tomshardware.com/pc-components/cpus/demand-for-data-center-cpus-has-surged-and-ai-agents-are-responsible-why-the-cpu-to-gpu-ratio-is-more-important-than-ever-for-hyperscalers?utm_source=edit-links&utm_medium=boxout&utm_term=ai-shortage)
- [Chip scarcity assaults auto industry amid the worsening Nexperia and DRAM crisis](https://www.tomshardware.com/tech-industry/chip-scarcity-assaults-auto-industry-amid-the-worsening-nexperia-and-dram-crisis?utm_source=edit-links&utm_medium=boxout&utm_term=ai-shortage)
- [The custom AI ASIC state of play](https://www.tomshardware.com/tech-industry/semiconductors/custom-ai-asics-examined-from-broadcom-to-mtia?utm_source=edit-links&utm_medium=boxout&utm_term=ai-shortage)
Prinz [picked the code](https://www.prinzai.com/p/gpt-6-astra-solves-a-wwi-german-radio) from a relatively famous list of 50 unsolved ciphers maintained by the German science blogging portal [Scienceblogs.de](https://scienceblogs.de/klausis-krypto-kolumne/unsolved-adfxvx-messages-from-world-war-i/). It was known to be “encoded using the ADFGVX method,” says the developer on their Substack.
Addressed to the German High Command and for the attention of an admiral or perhaps Naval Command, the ciphered message looks like gobbledygook, surely as intended. The German military at the time used a convoluted grid of letters that shuffled depending on the current keyword.
Latest Videos FromTom's Hardware
[Watch full video here:](https://www.tomshardware.com/tech-industry/artificial-intelligence/chatgpt-6-astra-cracks-108-year-old-unsolved-wwi-german-code-for-the-first-time-radio-message-sharing-enemy-movement-intelligence-had-evaded-decoding-1918-crimean-fleet-warning-verified-against-hms-canterbury-logs)
> GPT-6 Astra deciphered a 1918 German radio transmission that, to my knowledge, has never been deciphered before.The message below translates to:"EIN ENGLISCHER KREUZER EINLIEG X SEWASTOPOL X S4STEN X EIN GESCHWADER DER X ALLIIERTEN FOLGT 26STEN X"or, in English:"AN… pic.twitter.com/8kjDdI2Q5O[September 17, 2026](https://twitter.com/cantworkitout/status/2100608983492862201)
Astra solved the cipher using the word “TRUPPENVERSCHIEBUNG” as the key. This resulted in the decoded message: “EIN ENGLISCHER KREUZER EINLIEG X SEWASTOPOL X S4STEN X EIN GESCHWADER DER X ALLIIERTEN FOLGT 26STEN X.” Translated into English, we can at last understand that the radio message was the following alert: “AN ENGLISH CRUISER ARRIVED AT SEVASTOPOL ON THE ?4TH AN ALLIED SQUADRON FOLLOWS ON THE 26TH."
[Astra also](https://www.tomshardware.com/video-games/pc-gaming/developer-uses-gpt-6-astra-to-get-cod-black-ops-2-hijacked-map-running-natively-inside-minecraft-achieves-45fps-performance-using-minecrafts-opengl-context) checked its work against military logs. The details about the cruiser’s arrival time aligned with the arrival of the British cruiser HMS Canterbury in Sevastopol, [Crimea,](https://www.tomshardware.com/tech-industry/drones/nvidia-jetson-orin-guided-the-russian-ai-drone-that-killed-three-civilians-in-ukraine-forensic-teams-say) on November 24, 1918. So the ‘?’ was perhaps a typo made in transmission. However, the Allied squadron's arrival date was spot on (November 26), according to the historical records Prinz checked.
You may like
- [Portal
OpenAI’s GPT-6 Astra model autonomously completes Portal in 24 hours](https://www.tomshardware.com/tech-industry/artificial-intelligence/openais-gpt-6-astra-model-autonomously-completes-portal-in-24-hours-feat-cost-just-usd571-in-tokens)
- [Menacing cyborg
OpenAI's GPT-5.6 Sol and unreleased AI models break out of testing environment in 'unprecedented cybersecurity incident'](https://www.tomshardware.com/tech-industry/artificial-intelligence/openais-gpt-5-6-sol-and-unreleased-ai-models-break-out-of-testing-environment-in-unprecedented-cybersecurity-incident-rogue-agents-hacked-huggingfaces-production-servers-with-thousands-of-individual-actions-across-a-swarm-of-short-lived-sandboxes)
- [Getty
Rogue OpenAI models behind 'unprecedented cybersecurity incident' teamed up to break out of their testing environment — multiple agents left each other messages for months, communicating undetected](https://www.tomshardware.com/tech-industry/artificial-intelligence/rogue-openai-models-behind-unprecedented-cybersecurity-incident-teamed-up-to-break-out-of-their-testing-environment-multiple-agents-left-each-other-messages-for-months-communicating-undetected)
GPT-Astra hypothesizes that previous attempts to decipher this German message failed because code sleuths made an incorrect assumption. Before this decoding feat, it was thought that the keyword “TRUPPENVERSCHIEBUNG” was used only as a key starting December 9, 1918. Remember, this message was transmitted on November 29 of that year.
This [codebreaking](https://www.tomshardware.com/reviews/history-of-computers,4518-7.html) feat is a cool result and a good example of Astra’s flexible problem-solving capabilities.
Stay On the Cutting Edge: Get the Tom's Hardware Newsletter
Get Tom's Hardware's best news and in-depth reviews, straight to your inbox.
[Google Preferred Source](https://news.google.com/publications/CAAqLAgKIiZDQklTRmdnTWFoSUtFSFJ2YlhOb1lYSmtkMkZ5WlM1amIyMG9BQVAB)
*Follow* [*Tom's Hardware on Google News*](https://news.google.com/publications/CAAqLAgKIiZDQklTRmdnTWFoSUtFSFJ2YlhOb1lYSmtkMkZ5WlM1amIyMG9BQVAB)*, or* [*add us as a preferred source*](https://google.com/preferences/source?q=)*, to get our latest news, analysis, & reviews in your feeds.*
TOPICS
[See all comments (4)](https://www.tomshardware.com/tech-industry/artificial-intelligence/chatgpt-6-astra-cracks-108-year-old-unsolved-wwi-german-code-for-the-first-time-radio-message-sharing-enemy-movement-intelligence-had-evaded-decoding-1918-crimean-fleet-warning-verified-against-hms-canterbury-logs#xenforo-comments-3900589)
Mark Tyson
[Mark Tyson](https://www.tomshardware.com/author/mark-tyson)
News Editor
Mark Tyson is a news editor at Tom's Hardware. He enjoys covering the full breadth of PC tech; from business and semiconductor design to products approaching the edge of reason.
Read more
[Portal
Artificial Intelligence
OpenAI’s GPT-6 Astra model autonomously completes Portal in 24 hours](https://www.tomshardware.com/tech-industry/artificial-intelligence/openais-gpt-6-astra-model-autonomously-completes-portal-in-24-hours-feat-cost-just-usd571-in-tokens "OpenAI’s GPT-6 Astra model autonomously completes Portal in 24 hours")
[Menacing cyborg
Artificial Intelligence
OpenAI's GPT-5.6 Sol and unreleased AI models break out of testing environment in 'unprecedented cybersecurity incident'](https://www.tomshardware.com/tech-industry/artificial-intelligence/openais-gpt-5-6-sol-and-unreleased-ai-models-break-out-of-testing-environment-in-unprecedented-cybersecurity-incident-rogue-agents-hacked-huggingfaces-production-servers-with-thousands-of-individual-actions-across-a-swarm-of-short-lived-sandboxes "OpenAI's GPT-5.6 Sol and unreleased AI models break out of tes | Andune88 | 2395 | 225 |
| 🟧 echo.blog ⭐ | Reports using GPT-6 Astra to decipher a 1918 ADFGVX radio message about an English cruiser and an Allied squadron near Sevastopol, with the | Prinz | — | — |
| 🟧 hn | OpenAI GPT–6 Astra breaks Enigma message that has resisted solution since 2005 | sohkamyung | 738 | 443 |
| 🟧 hn | GPT-6 Astra Breaks an Old Enigma Message | frosk | 2 | 0 |
| 🟠 reddit | GPT-6 Astra helped decode a 217-year-old cipher letter to Napoleon's marshal OpenAI | ryanmerket | 158 | 16 |
| 🟧 hn | GPT-6 Astra breaks unsolved cipher to one of Napoleon's generals | MrBuddyCasino | 2 | 0 |
| 🟧 hn | I have used GPT-6 Astra to decipher two Catholic League letters from 1593 | tosh | 2 | 0 |
| 🟠 reddit | GPT-6 Astra helped decipher a Napoleonic military letter that remained unread for 217 years; it took just 6 hours singularity | Distinct-Question-16 | 747 | 119 |
2026-10-05T05:25:41Z
The episode's last live instrument decayed: seven consecutive velocity flags all point at the same Napoleonic post (53→730 over Oct 2-5, decelerating to ~1 pt/h and 0 comments/h), with no new evidence, platform, community, or outlet since Oct 2 — the magnitude-valve reading reflects the already-priced September crest plus one Reddit object, not expanding periphery. The verification question stayed in the lay-comment section for the entire arc and no cryptanalyst, reproduction, or archival check arrived within the window, so the case expires faded: genre lesson banked, specific claims unresolved.
2026-10-03T05:54:35Z
The new spike is the Napoleonic instance's second, better-performing Reddit post (1ww7uga, 290/69) amplifying the same weakest, detail-free instance — engagement duplicating known substance, not new evidence; notably its top comments are organic lay skepticism ('How do we know it got it right?', an observation-bias point that pre-modern ciphers draw little attack effort), so the verification vacuum is now visible to the mainstream audience itself rather than newly answered. Meaning unchanged: a corroborated bounded human-scaffolded demo genre with zero verification across four instances; heat stays low despite the magnitude-valve flag and 95th-percentile reading because the velocity again rests on one climbing Reddit object with HN echoes dead at 2/0, ~9% of the September peak, no new community or outlet, and the case 13 days past crest.
2026-10-02T23:24:09Z
evidence attached: reddit.post.1ww7uga — Second independent instance of GPT-6 Astra cracking long-unsolved historical ciphertext (1809 Napoleonic letter in 6 hours), corroborating the AI-assisted-historical-cryptanalysis spread.
2026-10-02T20:24:43Z
The Napoleonic instance's second wind tripled again (53→158 pts, 16 comments) and a fourth instance (1593 Catholic League letters, first-person HN report at 2/0) landed — but both add instance-count, not verification depth. The case's meaning is consolidating into a recurring human-scaffolded Astra-cipher demo genre that reliably attracts mainstream attention while no independent cryptanalyst or archivist has validated any instance; the persistent verification vacuum across four instances is now the most informative fact about it.
2026-10-02T19:29:58Z
evidence attached: hn.story.49936496 — Independent corroboration: a second GPT-6 Astra historical-cipher decipherment (1593 Catholic League letters) supports the AI-assisted-cryptanalysis hypothesis.
2026-10-01T15:36:40Z
The velocity spike is the Napoleonic instance's small second wind: the reddit post went 3→53 points and crossed to HN at 2/0 — platform spread of the weakest, least-detailed instance, with no verification substance. Absolute velocity (~8 pts/h aggregate vs ~448 peak, ~2%) keeps heat low despite the 90th-percentile peer reading, which is a small-cohort artifact of a young 53-point post; this is a thin echo on one sibling story, not periphery expansion. Meaning unchanged: corroborated bounded pattern, unverified specific claims.
2026-10-01T14:32:26Z
evidence attached: hn.story.49920832 — Second independent report of GPT-6 Astra cracking an unsolved historical cipher corroborates the AI-assisted cryptanalysis pattern in the open case.
2026-10-01T07:25:16Z
The Napoleonic cipher-letter post extends the Astra historical-cryptanalysis pattern to a third era and cipher family, but at 3 points and 2 comments it is marginal reinforcement, not new substance: no independent reproduction, inspectable procedure, or archival check has landed for any of the three instances, so the case's meaning is unchanged — corroborated bounded pattern, unverified specific claims, fading attention.
2026-10-01T07:24:07Z
evidence attached: reddit.post.1wus98d — Second independent instance of GPT-6 Astra decrypting a historical cipher, supporting the case's generalization from one-off to repeatable AI-assisted cryptanalysis.
2026-09-24T02:54:04Z
grounded: known/low — This is the position Scott already holds: a single-source frontier capability claim can only be defended at the evidence class of its weakest support, and press
2026-09-24T02:50:49Z
The Schneier post is a low-traction echo (score 2, no comments) of the already-covered Enigma sibling story, not new substance: it confirms the Astra-historical-cryptanalysis pattern has reached a credible independent commentator, but adds nothing to the WWI ADFGVX claim itself, which remains single-source and unverified. The case is now a corroborated pattern at pattern level but an attention story past its peak; engagement has collapsed from ~427 pts/h to ~0.3, so heat drops to low despite magnitude-valve eligibility — the periphery stopped expanding days ago.
2026-09-23T21:46:36Z
evidence attached: hn.story.49821081 — Schneier's report of GPT-6 Astra breaking an old Enigma message is a second independent instance corroborating the Astra historical-cryptanalysis pattern.
2026-09-23T18:08:22Z
The new HN activity is a sibling episode (a different Enigma message), and its best comments actually cut against the autonomy framing: a corrected account attributes that break to an anomalous key and transcription errors plus human-written solver tooling, not the model alone. That transfers only analogically to the WWI ADFGVX claim, which still has no independent reproduction or archival verification; its own engagement has plateaued, so the loud cross-platform spread already priced and alerted on 9/20 no longer justifies high heat.
2026-09-22T14:23:55Z
evidence attached: hn.story.49801324 — This independent HN discussion reports another claimed GPT-6 Astra cryptanalysis result, materially broadening the existing cryptanalysis episode if the linked artifact verifies it.
2026-09-20T05:23:46Z
The claim is becoming a widely circulating frontier-capability story, warranting attention to its spread rather than increased confidence in the result. Coverage and discussion still trace back to Prinz; neither independent cryptographic reproduction nor archival verification has arrived.
2026-09-19T21:33:57Z
grounded: known/low — The Scott-side lesson is already held in Witness Not Oracle and Mechanically Different Verifiers: a claimed discovery needs inspectable source evidence and chec
2026-09-19T21:28:54Z
case created — The specific ciphertext, key, and proposed plaintext make this a bounded, falsifiable capability claim rather than a general Astra performance story.