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Sierra Vista Hospital

listed as sierravistahospital.com · Claimed by Lockbit5 · listed 2 days ago

2d
Age
since listed · data leaked

Status timeline

  1. ListedJun 11, 2026
  2. Data leakeddate unknown

At a glance

Group
Lockbit5
Status
Data leaked
Country
United States
Sector
Healthcare
Listed on leak site
Jun 11, 2026

About the victim

AI dossier — public-source company profile

Sierra Vista Hospital is a private behavioral health facility located in Sacramento, California. The organization provides mental health and psychiatric services.

Industry
Healthcare - Behavioral Health
Address
Sacramento, California, US

Attack summary

Severity: critical — Healthcare provider with likely access to protected health information (PHI) and patient personally identifiable information (PII); confirmed data published by ransomware operator; behavioral health records are particularly sensitive.

LockBit5 claims to have compromised Sierra Vista Hospital and published data. The group indicates data exfiltration occurred, though specific data categories and scope are not detailed in the available post excerpt.

critical

Data the group says was taken

AI dossier — extracted from the leak post
  • patient records
  • healthcare data

What the group claims

Sierra Vista Hospital is a private behavioral health facility located in Sacramento, California, off...

Sources

Source

Indexed 2 days ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.

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Disclosure context

About lockbit5

Based on the provided data, LockBit5 appears to be a recently emerged ransomware operation first observed in December 2025, representing what may be a new iteration or rebrand within the LockBit ransomware ecosystem, with primary financial motivations evidenced by their targeting of high-value sectors. Given the LockBit naming convention and the timing of emergence, this group likely operates from Eastern Europe or Russia and may represent either a continuation of previous LockBit operations or a new affiliate group leveraging the established LockBit brand, though specific organizational details remain undocumented by major security agencies. While detailed attack methodologies have not been publicly documented by CISA, FBI, or major security researchers, the group's targeting pattern across 157 victims suggests a broad-spectrum approach focusing on technology, manufacturing, healthcare, and transportation sectors primarily in the United States, Brazil, Germany, Italy, and Mexico. Due to the group's recent emergence in December 2025, there are no publicly documented notable campaigns or major incidents reported by established threat intelligence sources, though the victim count indicates active operations. The group appears to be currently active based on the recent first observation date, though comprehensive analysis from major security agencies has not yet been published given the short timeframe since emergence. The group has been linked to 278 public disclosures across our corpus. First observed on a leak site on December 7, 2025; most recent post June 11, 2026. The operation is currently active.

Timeline of this disclosure

  • June 11, 2026sierravistahospital.com listed by lockbit5on the group's public leak site

Other recent disclosures by lockbit5

lockbit5 has been linked to 278 public victims on Darkfield. A sample of the most recent:

See the full lockbit5 dossier →

Sector and geography

This disclosure adds to ransomware activity in the Healthcare sector, which has 1,780 disclosures indexed across all operators we track. Geographically, sierravistahospital.com is reported in United States, a country with 2,714 ransomware disclosures in our corpus.

If your organisation is affected

A listing by lockbit5 means sierravistahospital.com appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

  • Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
  • Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
  • Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
  • Monitor for the data appearing on lockbit5's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.