People search Automatic Data Processing (ADP) data breach timeline because the brand sits on billions of accounts, credentials, and cloud workloads. BreachHistory indexes 1 Automatic Data Processing (ADP)-linked incident. This page maps every attested event through 2026 with internal links to canonical records.
Why Automatic Data Processing (ADP) breach history matters
Automatic Data Processing (ADP) operates in Technology (United States). Across indexed rows, recurring themes include mixed intrusion and disclosure events. Understanding the chronological pattern helps security teams, customers, and regulators separate confirmed disclosures from forum marketing.
Full timeline through 2026
2013 — — On August 9, McKesson notified the New Hampshire…
Cataloged incident. On August 9, McKesson notified the New Hampshire Attorney Generals Office that it was sending out notifications to some of their employees that their names, Social Security numbers, and gross wages may have been embedded in PDF tax statement files of other employees prepared by ADP for the firm. The problem, caused by a coding error, existed between 2010 and 2012, but only affected those who viewed their tax statement inlines and then downloaded and printed a copy of the pdf file. The coding error was detected on Exposed categories include Personal. No attested victim count is published for this row yet. See the automatic-data-processing-adp2013-vcdb1 and canonical BreachHistory entry.
Patterns and analysis
- Mixed intrusion and disclosure events — appears across multiple Automatic Data Processing (ADP) catalog entries; prioritize controls that address this class of failure.
- Record-count hygiene — BreachHistory indexes actor-cited figures separately from company-confirmed totals; read each row's technicalWriteup before treating counts as fact.
- 2026 monitoring — New disclosures roll into this timeline as they are verified or labeled unverified per catalog policy.
What to do if you may be affected
- Step 1: Enable phishing-resistant MFA on every account tied to this brand.
- Step 2: Use unique passwords and a password manager—breach rows often involve credential reuse.
- Step 3: Monitor official company breach notices and regulator filings, not dark-web downloads.
- Step 4: Review OAuth app permissions and revoke unused third-party integrations.
- Step 5: Bookmark the Automatic Data Processing (ADP) company page for new 2026+ disclosures.
Canonical BreachHistory hub
Explore every indexed row: breachhistory.com/automatic-data-processing-adp · Latest: automatic-data-processing-adp2013-vcdb1.
Sources: BreachHistory catalog (1 row for Automatic Data Processing (ADP)), company and regulator disclosures cited in individual breach records.