HackingHealthcareFinancial ServicesHealthcareVulnerability ExploitCapture Stored DataData ExfiltratedCustomer Data InvolvedDelayed DiscoveryHealth (basic)Identity (basic)PHIMediumContained

Premera Blue Cross

bd_728b41eaf5144b92 · schema v1 · pii pii-v1

Severity

Medium

Discovered

Jul 26, 2023

Filed

Apr 19, 2024

To disclose

38 weeks

Affected

2,384state residents only

Confidence

68%

Full breach record for Premera Blue Cross →7 incidents on file

Supplemental notice for Welltok, Inc. on behalf of Premera Blue Cross regarding a MOVEit Transfer server compromise. An unknown actor exploited vulnerabilities to access the server on May 30, 2023, exfiltrating names, addresses, DOBs, and member IDs. Welltok was alerted on July 26, 2023. Notices sent to 2,384 Washington residents on Jan 15, 2024.

J jump to incidentP pin to compareR raw source

Washington clock✗ WA AG >90d38 weeks discovery → filing

Incident timeline

undetected · 57 days

discovery → filing · 38 weeks / 268 days

May 30, 2023

Begins

Jul 26, 2023

Discovered

Apr 19, 2024

Filed

vs. sector median

+26 wks slower

Tracked as a single-filing incident — the only disclosure on record for this event so far.Confirmed2,384 affectedView incident

Name: Welltok, Inc.
norm: welltok
Domain: premera.com

Name: Premera Blue Cross
norm: premera blue cross
Domain: premera.com
Industry: HealthcarellmFinancial Servicesllm

Discovered: Jul 26, 2023
Breach occurred: May 30, 2023
Undetected for: 57 daysoccurrence → discovery
Materiality determined: —
Notification sent: Jan 15, 2024
Affected individuals: 2,384state-resident count only
Data types: Identity (basic)Health (basic)
Data elements: NameDate of birthHealth insurance ID
WA-stated cause: Cyberattack
WA-stated duration: lifecycle Unknowndexposure Unknownd
WA-stated discovery: Found after the fact
Attack vector: Misconfiguration
MITRE ATT&CK: T1190 Exploit Public-Facing ApplicationT1041 Exfiltration Over C2 Channel
Threat actor: ExternalFinancial
Regulator citations: Notified Washington State Office of the Attorney General
Initial access: exploit_public_facing

During the incident: Launched an additional investigation with the assistance of third-party cybersecurity specialists
Provided access to credit monitoring services for twelve (12) to twenty-four (24) months... through Experian
Providing impacted individuals with guidance on how to better protect against identity theft and fraud
Changes made: Reviewing and enhancing our existing policies and procedures related to data privacy
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 38 weeks(268 days from discovery to filing)
Compliance flags: WA AG >90d
Discovery-date grounding: letter-groundedThe discovery date is the detection date narrated in the notification letter — the defensible tier.

Status: No extraction artifact recorded for this disclosure.

Evidence ladder

Leak-site claim

Attacker assertion only. Establishes: claim date, group, alleged victim.

Press / market report

Unlocks: incident narrative, operational impact. Still no compliance clock.

State AG / regulator filingThis record

Unlocks: discovery date, data types, affected count, compliance clock.

SEC 8-K / victim statement

Unlocks: materiality, stated response, full audit trail. Ceiling removed.

Source URL: https://agportal-s3bucket.s3.amazonaws.com/databreach/BreachM16714.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Apr 19, 2024
Raw hash: bf72f74e27286c2277b944523624d4c85aa213345a6b664bbbc8da21117c18b2

Reporting entityWelltok, Inc.

Victim entityPremera Blue Cross

Incidentdiscovered Jul 26, 2023

Stated responseLaunched an additional investigation with the assistance of third-party cybersecurity specialists

ComplianceWA AG >90d

Extraction provenanceno artifact recorded

Source provenanceagportal-s3bucket.s3.amazonaws.com