jumonji-u.ac.jp

The Cyber Exposure Score is a published 0–100 formula built only from publicly observable signals. How this is calculated.

This domain scores better than 37% of the 106 Education organisations we track (cohort median 78). The sample is seeded from public incident data, not a random cross-section of the sector.

Posture summary

Ransomware leak-site listings (1)

This domain is named on the public leak site of a ransomware group. A leak-site post is a claim published by the group — not a verified fact, and not a statement by this organization. Groups list victims who did not pay, overstate what they hold, and occasionally name the wrong company. What is certain is that the listing itself is public.

Leak-site postings are collected here from 2026-07-30 onwards; an earlier listing would not appear above.

Source: Ransomware.live

Public attack surface (20 hostnames in Certificate Transparency)

Hostnames this organization published in public TLS certificates. Passive OSINT — nothing was scanned.

The hostname inventory — which forgotten hosts exist and where — is part of the complete audit for this domain.

Lookalike domains (2 registered of 105 checked)

Registered permutations of this domain. Existence is a fact, not an accusation — ownership and intent are not assessed. Those able to receive mail are the ones usable for invoice fraud and phishing. The Risk score (0–100) is a published formula weighing mail capability, registration age, spelling, what the homepage shows and phishing-feed hits, reduced when a name looks brand-owned (same registrar/nameservers, a redirect to this domain) or merely parked. How this is calculated.

Recommendations

• highEnforce DMARC

  No enforcing DMARC policy was observed. Publish a DMARC record and move to p=quarantine then p=reject to reduce spoofing.

• mediumEnable DKIM

  No DKIM record was found on common selectors. Enable DKIM signing.

• mediumEnable DNSSEC

  DNSSEC signing was not detected for this domain.

• criticalTreat data published on a leak site as disclosed

  This domain is named on safepay's public leak site on 2026-10-31. A leak-site post is a claim published by the group, not a verified fact — but the post itself is public, and if it is accurate the data is already out. Confirm the claim, then work from the assumption of disclosure: rotate every credential that touched the affected systems, invalidate active sessions, and check your notification duties under GDPR Art. 33/34.

• highMonitor lookalike domains

  1 registered lookalike domain(s) can receive mail, which is what makes them usable for invoice fraud and credential phishing. Monitor them and consider defensive registrations.