MalwareRetail & ConsumerRetailInfostealerData ExfiltratedCustomer Data InvolvedDelayed DiscoveryAuthenticationCredentialsFinancial accountIdentity (basic)MediumContained

Costco

bd_ac6baa130a725d30 · schema v1 · pii pii-v1

Severity

Medium

Discovered

Jul 17, 2015

Filed

Sep 22, 2015

To disclose

10 weeks

Affected

29,425state residents only

Linked

3 filings

Confidence

69%

Full breach record for Costco →2 incidents on file

Costco notified Washington AG of a security compromise at its online Photo Center host. An unauthorized party accessed the host system from June 19, 2014, to July 15, 2015, deploying malware that captured user input. Costco discovered the incident on July 17, 2015, when the host disabled payment processing. Approximately 29,425 Washington residents were notified. Compromised data included credit card details, names, addresses, emails, and passwords. Costco took the site offline, engaged forensic investigators, deleted stored card data, and offered credit monitoring.

J jump to incidentP pin to compareR raw source

Incident timeline

undetected · 393 days

discovery → filing · 10 weeks / 67 days

Jun 19, 2014

Begins

Jul 17, 2015

Discovered

Sep 22, 2015

Filed

vs. sector median

+2 wks slower

This filing is one of 3 about the same incident.View merged incident

Linked disclosures

Why this link?

Regulatory filings (2) · sorted by filing gap

New Hampshire State AGbd_5fe9eca8c784fcfe2015-09-22Candidate
Massachusetts State AGbd_97a5559f454bed292015-09-25 · +3dVerified

Name: Costco
norm: costco
Domain: costco.com

Name: Costco
norm: costco
Domain: costco.com
Industry: Retail & Consumerllm

Discovered: Jul 17, 2015
Breach occurred: Jun 19, 2014 – Jul 15, 2015
Undetected for: 393 daysoccurrence → discovery
Materiality determined: —
Notification sent: Sep 21, 2015
Affected individuals: 29,425state-resident count only
Data types: Identity (basic)Financial accountCredentials
Data elements: Username + passwordName
WA-stated cause: Unauthorized Access
WA-stated duration: lifecycle 300-399dexposure 300-399d
WA-stated discovery: Found after the fact
Attack vector: Third-Party / Supply Chain
MITRE ATT&CK: T1486 Data Encrypted for ImpactT1078 Valid AccountsT1119 Automated Collection
Threat actor: ExternalFinancial
Regulator citations: Notified Washington Attorney General’s Office
Initial access: external_remote_services

During the incident: Took the Site offline entirely
Engaged a third-party forensic vendor to investigate
Deleted all stored credit card information
Implemented new payment technology with enhanced security features
Worked with hosting company to implement security tools and tests
Informed credit reporting agencies and payment card networks
Required all users to reset their passwords
Arranged for identity theft recovery and credit monitoring services from ID Experts
Changes made: Rebuilt site with additional security measures at a variety of levels
Implemented new payment technology with enhanced security features
Worked with hosting company to implement security tools and tests
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 10 weeks(67 days from discovery to filing)
Compliance flags: — (clock not assessable for this source)

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 3 filings · 3 states

View merged incident ↗

New Hampshire State AGSep 22 · first

Washington State AGSep 22 · first · this page

Massachusetts State AG+3d

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/BreachM9587.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: Sep 22, 2015
Raw hash: 621929481e36968f7681b36481f9974637cfade5f4e95301f13f1438e8350fba

Linked disclosures

Regulatory filings (2) · sorted by filing gap

Reporting entityCostco

Victim entityCostco

Incidentdiscovered Jul 17, 2015

Stated responseTook the Site offline entirely

Complianceclock not assessable

Extraction provenanceno artifact recorded

Source provenanceagportal-s3bucket.s3.amazonaws.com