Social EngineeringHealthcareHealthcarePhishingData ExfiltratedCustomer Data InvolvedMulti-Stage ChainFinancial accountHealth (basic)Identity (basic)Government IDPHIMediumContained

MedicareCompare (MCUSA)

bd_1f5613c612bc962f · schema v1 · pii pii-v1

Severity

Medium

Discovered

Nov 19, 2024

Filed

May 6, 2025

To disclose

24 weeks

Affected

706state residents only

Confidence

69%

Regence BlueShield reports a phishing breach affecting 706 Washington residents. Business associate MedicareCompare (MCUSA) experienced unauthorized email access between Nov 5-21, 2024. Data included names, SSNs, DOBs, and medical history. MCUSA engaged forensic investigators, reset passwords, and implemented MFA.

J jump to incidentP pin to compareR raw source

Washington clock✗ WA AG >90d24 weeks discovery → filing

Incident timeline

undetected · 14 days

discovery → filing · 24 weeks / 168 days

Nov 5, 2024

Begins

Nov 19, 2024

Discovered

May 6, 2025

Filed

vs. sector median

+13 wks slower

Tracked as a single-filing incident — the only disclosure on record for this event so far.Confirmed706 affectedView incident

Name: Regence (Regence BS, Regence BSI and Regence BCBSO)
norm: regence regence bs regence bsi and regence bcbso

Name: MedicareCompare (MCUSA)
norm: medicarecompare
Industry: Healthcarellm

Discovered: Nov 19, 2024
Breach occurred: Nov 5, 2024 – Nov 21, 2024
Undetected for: 14 daysoccurrence → discovery
Materiality determined: —
Notification sent: —
Affected individuals: 706state-resident count only
Data types: Identity (basic)Government IDHealth (basic)PHI
Data elements: NameSocial Security numberDriver's licence numberFinancial account numberDate of birthHealth insurance IDMedical information
WA-stated cause: Cyberattack
WA-stated duration: lifecycle 1-99dexposure 1-99d
WA-stated discovery: Found while ongoingContained same day
Attack vector: Phishing
MITRE ATT&CK: T1566.002 Spearphishing LinkT1078 Valid AccountsT1114 Email Collection
Threat actor: External
Regulator citations: MCUSA initially notified the United States Department of Health and Human Services Office for Civil Rights (OCR) on Mar. 21, 2025MCUSA submitted media notification in the State of Washington via PR Newswire submission on Mar. 21, 2025
Third party: via MedicareCompare (MCUSA)
Initial access: phishing_link

During the incident: Engaged a third-party forensic specialist to investigate
Conducted password resets for the impacted accounts
Implemented Multi-Factor Authentication for all licensed accounts
Changes made: Implemented additional cybersecurity measures
Reviewed existing security policies to further protect against similar events moving forward
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 24 weeks(168 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/BreachA33223.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: May 6, 2025
Raw hash: 905eb012a73b5460339eebde151ff2be8960da3a8677ce15c28ac917b7ebf33d

Reporting entityRegence (Regence BS, Regence BSI and Regence BCBSO)

Victim entityMedicareCompare (MCUSA)

Incidentdiscovered Nov 19, 2024

Stated responseEngaged a third-party forensic specialist to investigate

ComplianceWA AG >90d

Extraction provenanceno artifact recorded

Source provenanceagportal-s3bucket.s3.amazonaws.com