HackingStolen CredentialsData ExfiltratedData EncryptedCustomer Data InvolvedDelayed DiscoveryMulti-Stage ChainNation State SuspectedTargetedIDENTITY_BASICIDENTITY_GOVERNMENTCREDENTIALSAUTHENTICATIONCriticalContained
Yahoo Inc.
bd_6f04f3fd176af76f · schema v1 · pii pii-v1
Full breach record for Yahoo Inc. →Yahoo! Inc. disclosed a data breach affecting over 500 million user accounts. Unauthorized third parties stole data in August 2013, including names, emails, DOBs, hashed passwords, and security questions. A separate incident involved state-sponsored actors forging cookies in 2015-2016. Yahoo worked with law enforcement, forced password resets, invalidated security questions and forged cookies, and hardened systems. The incident is distinct from a September 2016 disclosure.
California clockDiscovered Nov 1, 2016 → Notified Dec 14, 201643d ✓ CA 60-day OK6 weeks discovery → filing
⚠ unattributedNo provenance was recorded for this discovery date and it matches no other date on the record. It may be correct, but it is not independently grounded.
Tracked as a single-filing incident — the only disclosure on record for this event so far.Confirmed500,000,000 affectedView incident
Source provenance
- Source URL
- https://oag.ca.gov/ecrime/databreach/reports/sb24-65449
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
- Filed at
- Dec 14, 2016
- Raw hash
- 2983d7343a4777c7563b8defa4119abaa3e34909def108addcad44e599e2cfcf
Reporting entity
- Name
- Yahoo Inc.norm: yahoo
- Domain
- yahooinc.com
Victim entity
- Name
- Yahoo Inc.norm: yahoo
- Domain
- yahooinc.com
Incident
- Discovered
- Nov 1, 2016
- Materiality determined
- Dec 14, 2016
- Notification sent
- Dec 14, 2016
- Affected individuals
- 500,000,000
- Data types
- IDENTITY_BASICIDENTITY_GOVERNMENTCREDENTIALSAUTHENTICATION
- Attack vector
- Unauthorized Access
- MITRE ATT&CK
- T1078 Valid AccountsT1078.004 Cloud Accounts
- Threat actor
- ExternalEspionage
- Regulator citations
- Working closely with law enforcement
- Initial access
- valid_credentials
Compliance
- Time to disclose
- 6 weeks(43 days from discovery to filing)
- Compliance flags
- CA 60-day OK · 43d
- Discovery-date grounding
- unattributedNo provenance was recorded for this discovery date and it matches no other date on the record. It may be correct, but it is not independently grounded.
- Clock breakdown
Statute Window Elapsed Threshold Status California Discovered: Nov 1, 2016→ Notified: Dec 14, 201643d 60 days (analyst band, pre-2026 discoveries) CA 60-day OK
Extraction provenance
- Status
- No extraction artifact recorded for this disclosure.