Japan Pension Service data leak
Add to my breach checkMade public · 1,250,000 records
What leaked4
Hard to replace
- Home or delivery address
Permanent
- National ID or tax number
- Date of birth
- Full name
- National ID or tax numberBasic Pension Number · kiso nenkin bango, in every leaked record
- Date of birthabout 1.22 million of the 1.25 million records
- Home or delivery addressabout 52,000 records
To-dos
None of the harms this check covers.
What happened next18 events
- Undetected 2 events20 days · show events
- Response 12 eventsNotice in 6 days · show events
- RemedyNone on record
- Penalty 4 eventsOngoing · show events
- DisputesNone on record
- Published its business improvement plan, including strengthened information security
- The Minister of Health, Labour and Welfare issued a business improvement order to the agency's president
- MHLW published its own organisational and security reform plan
- Sanctions on officers: reprimands for the president, vice president and systems director, a warning for another director; the three returned 20% of monthly pay for two months and June bonuses were withheld for all executives
- The head of the Cybersecurity Strategic Headquarters (Chief Cabinet Secretary) issued a recommendation to the Minister of Health, Labour and Welfare
13 more
- The MHLW verification committee published its report
- Announced that new Basic Pension Numbers would be mailed from 24 August to about 960,000 affected people · changed numbers; no action needed
- The government's Cybersecurity Strategic Headquarters published its root-cause investigation
- The agency published its internal investigation report
- MHLW set up a verification committee chaired by a former Supreme Court justice
- The president apologised in the letter to affected people
- Began mailing letters of apology, starting with about 9,000 pension recipients whose four data items leaked
- From 2 June, pension procedures for affected people require identity confirmation; affected people's pension numbers to be changed
- Opened a dedicated free-dial call centre the same day
- Announced about 1.25 million leaked records: Basic Pension Number with name, and in most cases date of birth and in some address
- Confirmed that personal data had been sent out after a virus email compromised staff computers
- Intrusion began
- While the attacks continued from 8 May, the agency updated antivirus software, cut internet access at affected sites and consulted the police
- Company
- Japan Pension Service
- When it happened
- Company detected it
- Made public
- Notice
- Leak confirmed
- Affected
- 1,250,000 records · Japan Pension Service, June 2015
Sources
- 日本年金機構 company notice, (opens in a new tab)checked October 22, 2026
- 日本年金機構 company notice, (opens in a new tab)checked October 22, 2026
- 厚生労働省 regulator (opens in a new tab)checked October 22, 2026
- 日本年金機構 company notice, (opens in a new tab)checked October 22, 2026