A string of personal data breaches in Japan has driven sales of DAISO’s paper “Password Management Notebook” up week by week since late October. The 100-yen shop is temporarily out of stock. (Previously: Japanese forex host GMO hacked and hit with ransomware; unlucky users lose 4 million yen in 2 seconds) (Background: How can you protect your digital assets? The 15-step checklist kept by an OpenAI founder) Key points DAISO’s 110-yen password notebook is out of stock, with restocking expected within November Japan reported 193 cyberattack-related data breaches in October, the highest monthly total since 2022 Up to 1.13 million email addresses may have been exposed at Monex Securities A string of personal data breaches in Japan has driven DAISO, the 100-yen shop, to sell out of its paper “Password Management Notebook.” Daiso Industries, which operates DAISO, responded to an interview on November 11. The company said notebook sales have grown week by week since late October, and that it expects to restock within November while adjusting production to increase output. The notebook is listed for 110 yen, tax included (about NT$23 at the November 14 exchange rate), on DAISO’s online store, and has 38 pages. Its pages are for writing down account names and passwords for different websites by hand. DAISO has not disclosed specific sales figures, saying only that the recent growth was “surprising even to the person in charge of development.” The product page on the online store also showed it as sold out on November 14. An X post gets people talking The discussion began with a post by an X user on the evening of November 1 (Japan time). The post read: “I bought a password management notebook at DAISO. I used to think, who would buy something like this? But I think analog (handwritten) management is the best way in this day and age.” “I bought a password management notebook at DAISO. I used to think, who would buy something like this? But I think analog management is the best way in this day and age…” pic.twitter.com/FybHLhjFiv — ひなパパ (@hina_money35) November 1, 2026 DAISO has been releasing this notebook since autumn 2020. It was initially aimed at older people and those who were not accustomed to managing passwords on digital devices. DAISO said the peace of mind that comes from keeping records on paper that is not connected to the internet is “attracting renewed attention.” The company currently has no plans to launch other password-related products and will focus first on keeping this notebook in stock. October breaches hit their highest level since 2022 ITmedia noted that the notebook’s sales began rising around the same time the number of publicly disclosed data breaches in Japan surged. Japanese market research firm MM Research Institute counted 72 information breach incidents caused by cyberattacks in August and 81 in September. The number jumped to 193 in October—the highest monthly total since 2022, and more than the combined total for August and September. Leaks of authentication information such as passwords and login IDs are also increasing. MM Research Institute estimates that about 161 million records had been exposed by the end of October this year, around 31 times the 5.14 million for all of 2025. This figure adds together the types of data exposed in each incident, so some records may be counted more than once. MM Research Institute noted that leaked account credentials can be used in “credential stuffing” attacks, in which the same login details are tried on other websites. Major incidents have also continued to emerge. According to ITmedia, software vendor SourceNext announced on October 15 that its membership system had been accessed without authorization. Up to about 22.52 million member records, including passwords, may have been leaked. Online brokerage Monex Securities also announced on November 13 that an account-opening system operated by an outsourcing provider had been accessed without authorization. Up to 1.13 million email addresses and 1,592 images of identity documents may have been exposed. These images include the front of My Number cards, both sides of driver’s licenses, and selfies. The email addresses belong to people who applied to open an account online after October 16, 2019, including applicants who did not complete the account-opening process. Monex Securities said account IDs, login passwords, and trading passwords are stored in separate databases, and that it has confirmed they were not leaked. It has also found no unauthorized transactions. IPA warns that paper records cannot prevent breaches at service providers ITmedia also spoke with Japan’s Information-Technology Promotion Agency (IPA), which promotes cybersecurity. The IPA said it does not necessarily oppose managing passwords on paper. It recommends using a different password for each service, made up of uppercase and lowercase letters and numbers, and around 15 characters long. The IPA also pointed out that carrying a notebook around creates a risk of losing it or having someone look at it. If passwords are leaked from a service provider’s system, keeping a paper record at home cannot prevent that. Frequently asked questions How much does DAISO’s password management notebook cost, and when will it be restocked? It costs 110 yen, tax included (about NT$23), and has 38 pages. DAISO said sales have grown week by week since late October and the notebook is temporarily out of stock. Restocking is expected within November, and production is being adjusted to increase output. Is it safe to write passwords in a paper notebook? Japan’s IPA does not necessarily oppose using paper, but a notebook can be lost or viewed by someone else, and paper records cannot prevent a breach at a service provider. The IPA recommends using a different password for each service, making each around 15 characters long, and enabling multifactor authentication. Related reports Personal data of 690,000 ezTravel users hacked and leaked; don’t trust calls about “order irregularities” 46,000 TSMC employees’ personal data offered on the dark web for 3 bitcoins; company acknowledges leak but says its systems were not compromised Blockchain analytics firm Chainalysis also hit by a security incident: personal data including customers’ full names and email addresses leaked This article, “Personal data breaches keep piling up in Japan; DAISO’s ‘paper password notebook’ sells out,” was first published by BlockTempo (動區動趨—The most influential blockchain news media).