Nostrum
bd_6f7159c6684efe48 · schema v1 · pii pii-v1
Full breach record for Nostrum →Press / market disclosure — not a breach-notification filing
A media or market posting that confirms an incident but carries no breach-notification fields, so compliance clocks aren't assessable. The summary below is extracted from the coverage and machine-translated to English — verify against the source.
Summary
machine-translatedNostrum hit by ransomware attack, learning support service also suspended | ScanNetSecurity. Nostrum Co., Ltd.: Nostrum was the victim of a ransomware attack on its servers, which occurred on May 8. The attack breached the network via VPN on April 19 around 5 a.m., encrypting the data of internal servers and rendering them inoperable, which also interrupted its learning support service. The company reported the incident to the police and the Personal Information Protection Authority, hired an external company to monitor a leak site, and conducted investigations and repairs with security experts. They are also rebuilding the system on new infrastructure for a rapid restart of services. The attack was claimed on April 27 by The Gentlemen. Linked ransomware group: thegentlemen.
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Incident timeline — mostly unverified
? — ?
Breach window unknown
Apr 19, 2026
Press report
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Corroborated · see linked filings
Compliance clocks stay unassessable until a regulatory filing lands. Dashed segments fill in automatically when corroboration arrives.
Attack → press
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Compliance clock
Not assessable
Linked disclosures
Why this link?Ransomware claims (1)
- Leak Sitethegentlemenbd_ff261fee6341fc802026-04-27 · +8dCandidate
Evidence ladder
Attacker assertion only. Establishes: claim date, group, alleged victim.
Unlocks: incident narrative, operational impact. Still no compliance clock.
Unlocks: discovery date, data types, affected count, compliance clock.
Unlocks: materiality, stated response, full audit trail. Ceiling removed.
Source ceiling
- incident type + narrative only (may be machine-translated)
- discovery date
- materiality
- affected count
- data types
- compliance clock
The ✕ fields stay blank until a regulatory filing or victim disclosure lands.
thegentlemen
According to ransomware.live, The Gentlemen is a RaaS group that emerged in July–August 2025, rapidly claiming over 320 victims across 17+ countries by offering affiliates a 90% revenue share, deploying a Go-based locker against Windows, Linux, NAS, and BSD systems; a compromised C2 server in 2026 revealed more than 1,570 linked victims.