HackingFinancial ServicesProfessional ServicesFinanceVulnerability ExploitStolen CredentialsCapture Stored DataZero-DayData ExfiltratedRansom DemandedMulti-Stage ChainLateral Movement ObservedDelayed DiscoveryHealth (basic)Identity (basic)Government IDPHICVE-2021-27852HighContained

Aon

bd_bf4952e393f83732 · schema v1 · pii pii-v1

Severity

High

Discovered

Feb 25, 2022

Filed

May 26, 2022

To disclose

13 weeks

Affected

3,328state residents only

Linked

14 filings

Confidence

69%

Full breach record for Aon →11 incidents on file

Aon Corporation PLC disclosed a cyber event where an unauthorized third party exploited a zero-day vulnerability (CVE-2021-27852) to gain access to systems between Dec 2020 and Feb 2022. The actor staged and exfiltrated unstructured data containing PII (names, SSNs, driver's licenses). Aon reported to law enforcement, engaged forensic experts, and notified 3,328 Washington residents, offering 24 months of credit monitoring.

J jump to incidentP pin to compareR raw source

Washington clock⏱ WA AG >30d13 weeks discovery → filing

⚠ AG web formThe discovery date came from the AG web-form field, which is systematically later than the detection date stated in the letter. Treat the clock as indicative.

Incident timeline

undetected · 423 days

discovery → filing · 13 weeks / 90 days

Dec 29, 2020

Begins

Feb 25, 2022

Discovered

May 26, 2022

Filed

vs. sector median

+4 wks slower

This filing is one of 14 about the same incident.View merged incident

Linked disclosures

Why this link?

Ransomware claims (1)

Leak Sitedispossessorbd_d4e9fb69d737f7a62022-07-03 · +38dVerified by operator

Regulatory filings (9) · sorted by filing gap

HHS OCRbd_1659c519cbbc91942022-05-26Verified by operator
Oregon State AGbd_a34b45e6fa897e082022-05-26Verified
California State AGbd_a3a4b3bd3ddac8fc2022-05-26Verified
Indiana State AGbd_fde32f8598ecaa8b2022-05-27 · +1dVerified

Show 5 more filings ↓up to 36d gap

New Hampshire State AGbd_bed97e68b6fb0b6c2022-05-31 · +5dVerified by operator
New Hampshire State AGbd_5ba6400246ccb57f2022-06-13 · +18dVerified by operator
Montana State AGbd_f3bea3092e6d8ecc2022-06-13 · +18dVerified by operator
Maine State AGbd_ee7cfc9886fcd7132022-06-24 · +29dCandidate
Maine State AGbd_83344b1fed7fdb7a2022-07-01 · +36dCandidate

Showing first 10 of 13 linked disclosures.

Name: Norton Rose Fulbright US LLP
norm: norton rose fulbright us

Name: Aon
norm: aon
Domain: aon.com
Industry: Financial ServicesllmProfessional Servicesllm

Discovered: Feb 25, 2022
Breach occurred: Dec 29, 2020 – Feb 26, 2022
Undetected for: 423 daysoccurrence → discovery
Materiality determined: Feb 25, 2022
Notification sent: May 27, 2022
Affected individuals: 3,328state-resident count only
Data types: Identity (basic)Government IDHealth (basic)
Data elements: NameSocial Security numberDriver's licence numberHealth insurance ID
WA-stated cause: Unauthorized Access
WA-stated duration: lifecycle 400-499dexposure 400-499d
WA-stated discovery: Found while ongoing
Attack vector: Unauthorized Access
MITRE ATT&CK: T1190 Exploit Public-Facing ApplicationT1078 Valid AccountsT1119 Automated CollectionT1074 Data StagedT1041 Exfiltration Over C2 Channel
Threat actor: ExternalFinancial
Regulator citations: Reported the event to federal law enforcement and has been supporting their investigation ever since
Initial access: exploit_public_facing
CVE references: CVE-2021-27852

During the incident: Engaged third-party advisors, incident response professionals and counsel
Reported the event to federal law enforcement
Engaging external security experts to investigate the event
Enhancing security, including upgrading and expanding internal and external multi-factor authentication (MFA)
Reviewing and updating account permissions
Resetting user passwords firm-wide
Enhancing security by deploying CrowdStrike Falcon, a leading Endpoint Protection Platform
Offering 24 months of complimentary credit monitoring and fraud protection services
Changes made: Engaging external security experts to investigate the event
Enhancing security, including upgrading and expanding internal and external multi-factor authentication (MFA)
Reviewing and updating account permissions
Resetting user passwords firm-wide
Enhancing security by deploying CrowdStrike Falcon, a leading Endpoint Protection Platform
Source: Quoted from the filing itself, not independently verified.

Time to disclose: 13 weeks(90 days from discovery to filing)
Compliance flags: WA AG >30d
Discovery-date grounding: AG web formThe discovery date came from the AG web-form field, which is systematically later than the detection date stated in the letter. Treat the clock as indicative.

Status: No extraction artifact recorded for this disclosure.

Filing propagation · 10 filings · 8 states

View merged incident ↗

HHS OCRMay 26 · first

Oregon State AGMay 26 · first

California State AGMay 26 · first

Washington State AGMay 26 · first · this page

Indiana State AG+1d

New Hampshire State AG+5d

New Hampshire State AG+18d

Montana State AG+18d

Maine State AG+29d

Maine State AG+36d

Pattern: first filing May 26 (IL), last Jul 1 (ME) — a 36-day rolling notification. Rolling spreads often mean counsel is filing as thresholds trip per state. Why this link?

Cascade drawn from the first 10 linked disclosures of 13 — the full spread may be wider.

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/BreachA10440.pdf
DisclosureLens links to the originating regulator URL — full filing bodies are not redistributed from public surfaces (§4.5).
Filed at: May 26, 2022
Raw hash: 2f489a6110d8a4576d4909a890791ac5899f440e693b7c55e8e314c1d9424c7f

Linked disclosures

Ransomware claims (1)

Regulatory filings (9) · sorted by filing gap

Reporting entityNorton Rose Fulbright US LLP

Victim entityAon

Incidentdiscovered Feb 25, 2022

Stated responseEngaged third-party advisors, incident response professionals and counsel

ComplianceWA AG >30d

Extraction provenanceno artifact recorded

Source provenanceagportal-s3bucket.s3.amazonaws.com