UMSA Listed by ShadowByt3$ Ransomware Group: Ransomware Claim — What’s Alleged & What To Do

On February 25, 2026, the ransomware group ShadowByt3$ listed UMSA on its leak site and referenced a file named UMSA_LEAK.7z said to contain internal files taken during a ransomware incident. The number of individuals whose information may be involved remains unknown, and no further confirmation of the listing or details on the file contents have been made public. For anyone connected to UMSA, the incident raises the possibility that operational records held by the organisation could now circulate outside authorised channels.

Breaking down the breach

The only confirmed public information is the February 25, 2026 listing itself and the reference to the compressed file UMSA_LEAK.7z. No statement has been issued on the date of the underlying intrusion, the method used to gain access, the volume of data taken, or whether any data were later published. The number of people affected is recorded as unknown.

The group behind it: ShadowByt3$

ShadowByt3$ is a ransomware operator that maintains a leak site where it lists organisations it claims to have targeted. Such groups commonly encrypt systems and threaten to release stolen material if ransom demands are not met. The listing of UMSA constitutes the group’s claim; independent verification of the claimed access or the contents of UMSA_LEAK.7z has not been reported.

UMSA and its sector

Public detail on UMSA is limited in available breach reporting. Organisations of this type routinely maintain internal administrative, operational and personnel records as part of their normal activities. A breach involving such records can expose information that was not intended for external distribution, regardless of the organisation’s size or specific function.

The information in question

The listing describes the material only as internal files exfiltrated in a ransomware attack. No further breakdown of file categories, such as personal identifiers, financial records or communications, has been supplied. Without additional disclosure from either the organisation or confirmed analysis of the file, the precise nature of the data remains unconfirmed.

What's at stake

Internal files can contain details that, if misused, may assist in further targeting of the organisation or individuals referenced in those records. For the people whose information appears in such material, possible consequences include unsolicited contact or attempts to exploit the data in unrelated scams. The organisation itself faces the task of assessing the scope of any access and determining what follow-up steps, if any, are required under applicable data-protection obligations.

Were you affected?

Individuals who have had contact with UMSA can begin by monitoring their email accounts for unusual activity and reviewing any recent password-reset requests. A practical first step is to run a free exposure scan of the email address associated with UMSA to check whether it appears in known breach datasets. Organisations in similar situations often advise affected parties to remain alert for targeted phishing attempts that reference the incident.

AICompiled with AI assistance from public sources and published under our editorial standards.