Illinois K-12 Email Security Intelligence:
DNS Authentication Profiling of 1035 School District LEAs

Lokentra Research Team

Lokentra U.S. Email Security Index (ESI) — State Intelligence Series

April 22, 2026

research@monitorworkspace.com • monitorworkspace.com/scorecard

Abstract

We present DNS email security profiling for 1035 K-12 LEAs in Illinois, of which 846 have active domains (81.7% coverage). Domains were scored on the Lokentra 100-point Email Security Index (ESI) rubric (SPF 30 pts + DKIM 30 pts + DMARC 40 pts). Illinois K-12 districts achieve an average ESI score of 49.5/100, with 27.1% earning Grade A or B (strong posture) and 31.2% receiving Grade F (minimal authentication). Only 49.2% have any DMARC record, and just 26.4% have DMARC at an enforcement level (quarantine or reject) — leaving 50.8% of districts fully vulnerable to email domain spoofing. This report provides entity-level data for all 846 scored domains including provider classification, authentication status, and ESI score, sourced from NCES CCD 2024-2025 and live DNS resolution conducted April 22, 2026.

Keywords: Illinois, K-12 email security, DMARC, SPF, school district cybersecurity, DNS authentication, Google Workspace, education technology

1. Dataset Overview

Table 1. Illinois K-12 Dataset Summary
Metric	Value
Total K-12 LEAs in state	1035
Regular school districts	857
Charter LEAs	12
Other LEA types (state-operated, regional, etc.)	166
LEAs with active internet domain	846 (81.7%)
Domains DNS-profiled	846
Data freshness (NCES CCD)	2024-2025 school year
DNS scan date	April 22, 2026

2. The Human Impact: Populations at Risk

To estimate human exposure, NCES national averages are applied to CCD 2024-2025 operational school counts: 381 students per school, 51 staff per school, and 2 parents or guardians per student. Illinois K-12 districts collectively operate approximately 4,396 schools.

Table 2. Estimated Population Exposure from K-12 Email Security Gaps — Illinois
Population	Total in Dataset	At Risk (No DMARC, 50.8%)	Critically Exposed (Grade F, 31.2%)
Students	1,674,876	850,837	522,561
Parents and guardians	3,349,752	1,701,674	1,045,122
Staff and educators	224,196	113,891	69,949
Total people	5,248,824	2,666,402	1,637,633

Estimates based on NCES national averages. Individual district enrollment data can be linked via NCES LEAID for precise counts.

3. Authentication Findings

3.1 Protocol Adoption

Table 3. Email Authentication Protocol Adoption — Illinois K-12
Protocol	Illinois	National K-12 (ESI)	vs. National
SPF (any configuration)	76.5%	79.7%	-3.2pp
DKIM (key published)	58.0%	59.6%	-1.6pp
DMARC (any policy)	49.2%	55.5%	-6.3pp
DMARC at enforcement (quarantine/reject)	26.4%	~21.0%	+5.4pp
DMARC at reject (full enforcement)	10.4%	~12.2%	-1.8pp
No MX records (not receiving email)	8.4%	~10.0%	-1.6pp

3.2 ESI Grade Distribution

Table 4. ESI Score Grade Distribution — Illinois K-12
Grade	Score	Districts	Share	Interpretation
A	90–100	109	12.9%	Full enforcement
B	70–89	120	14.2%	Strong posture
C	50–69	259	30.6%	Partial protection
D	30–49	94	11.1%	Weak configuration
F	0–29	264	31.2%	Minimal/no authentication
Average score		49.5 / 100

3.3 Email Provider Distribution

Table 5. Email Provider Distribution — Illinois K-12 (top providers)
Provider	Districts	Share
Google Workspace	635	75.1%
Microsoft 365	68	8.0%
GoDaddy	10	1.2%
Barracuda	8	0.9%
Mimecast	4	0.5%
Sophos	2	0.2%

4. District-Level Data

4.1 Top Performing Districts (Best ESI Scores)

Table 6. Top 15 Illinois K-12 Districts by ESI Score
District	Domain	County	Provider	SPF	DKIM	DMARC Policy	Score	Grade
Streator ESD 44	`ses44.net`	LaSalle County	Google Workspace	✓	✓	reject	100	A
De Kalb ROE	`dekalbcounty.org`	DeKalb County	Barracuda	✓	✓	reject	100	A
Heartland Region	`tech-academy.org`	Macon County	Microsoft 365	✓	✓	reject	100	A
Township HSD 214	`d214.org`	Cook County	Google Workspace	✓	✓	reject	100	A
Barrington CUSD 220	`barrington220.org`	Cook County	Google Workspace	✓	✓	reject	100	A
Big Hollow SD 38	`bighollow.us`	Lake County	Google Workspace	✓	✓	reject	100	A
Bourbonnais SD 53	`besd53.org`	Kankakee County	Google Workspace	✓	✓	reject	100	A
Central CUSD 301	`central301.net`	Kane County	Google Workspace	✓	✓	reject	100	A
Elmhurst SD 205	`elmhurst205.org`	DuPage County	—	✓	✓	reject	100	A
Eureka CUD 140	`district140.org`	Woodford County	Google Workspace	✓	✓	reject	100	A
Keeneyville SD 20	`esd20.org`	DuPage County	Microsoft 365	✓	✓	reject	100	A
Joliet Twp HSD 204	`jths.org`	Will County	Microsoft 365	✓	✓	reject	100	A
Will County SD 92	`d92.org`	Will County	Google Workspace	✓	✓	reject	100	A
Morton Grove SD 70	`mgsd70.org`	Cook County	Google Workspace	✓	✓	reject	100	A
Brown County CUSD 1	`bchornets.com`	Brown County	Microsoft 365	✓	✓	reject	100	A

4.2 Districts Most in Need of Improvement (Lowest ESI Scores)

Table 7. Bottom 15 Illinois K-12 Districts by ESI Score
District	Domain	County	Provider	SPF	DKIM	DMARC Policy	Grade
IDJJ Sch Dist 428	`idoc.state.il.us`	Cook County	—	✗	✗	—	F
Norris City-Omaha-Enfield CUSD 3	`ncoehs.white.k12.il.us`	White County	—	✗	✗	—	F
Gallatin CUSD 7	`roe20.k12.il.us`	Gallatin County	Google Workspace	✗	✗	—	F
Georgetown-Ridge Farm CUD 4	`grf.k12.il.us`	Vermilion County	—	✗	✗	—	F
A-C Central CUSD 262	`a-ccentral.com`	Cass County	—	✗	✗	—	F
Henry-Senachwine CUSD 5	`hscusd5.org`	Marshall County	—	✗	✗	—	F
Bureau Valley CUSD 340	`bv340.com`	Bureau County	GoDaddy	✗	✗	—	F
South Central CUD 401	`southcentralschools.org`	Marion County	Google Workspace	✗	✗	—	F
Adam/Brwn/Cass/Morgn/Pik/Sctt ROE	`roe1.org`	Adams County	—	✗	✗	—	F
Cowden-Herrick CUSD 3A	`cowden-herrick.k12.il.us`	Shelby County	—	✗	✗	—	F
McHenry ROE	`mchenryroe.org`	McHenry County	—	✗	✗	—	F
River Ridge CUSD 210	`riverridge210.org`	Jo Daviess County	—	✗	✗	—	F
Prairie Crossing Charter School	`prairiecrossingcharterschool.org`	Lake County	Google Workspace	✗	✗	—	F
Bond Fayette Effingham EFE 410	`okaw.us`	Fayette County	Google Workspace	✗	✗	—	F
Nippersink SD 2	`nippersinkdistrict2.org`	McHenry County	—	✗	✗	—	F

4.3 County-Level Summary (Top 10 Counties by District Count)

Table 8. Illinois County Distribution
County	Districts	Website Coverage
Cook County	177	76.8%
Lake County	50	86.0%
DuPage County	48	85.4%
Will County	36	86.1%
St. Clair County	33	81.8%
LaSalle County	29	86.2%
McHenry County	22	81.8%
Peoria County	21	90.5%
Tazewell County	21	90.5%
Champaign County	18	77.8%

5. Policy Implications

These findings identify specific, actionable gaps in Illinois's K-12 email security posture. The 50.8% DMARC gap represents districts that can be impersonated by any sender, enabling phishing campaigns targeting parents, students, and educators with no authentication failure. Key observations:

Immediate risk: 264 districts (31.2%) have Grade F scores, indicating minimal or no email authentication. These represent the highest-priority remediation targets.
Mid-tier stagnation: 259 districts (30.6%) are in the C range — typically have SPF but no DMARC or weak DMARC (p=none). Upgrading to p=quarantine would move them to B without infrastructure changes.
Provider leverage: Google Workspace (used by 75.1% of scored districts) provides automated SPF/DKIM configuration. Districts on Google Workspace with Grade F scores have misconfigured or missing DMARC — a free and simple fix.

6. Data Availability

The full Illinois K-12 dataset — 1035 entities with NCES CCD enrichment (phone, address, grade span, school count, LEAID) and DNS authentication profiles — is available as part of the Lokentra ESI State Pack.

Table 9. Licensing Tiers
Tier	Scope	Suggested Use
State Pack: Illinois	All 1035 K-12 LEAs, full DNS profile + CCD enrichment	Regional studies, state policy, outreach
K-12 National	All 50 states, 20,021+ K-12 LEAs	National K-12 cybersecurity research
Full Registry	801,359+ entities across all sectors	Comprehensive multi-sector research
API + Updates	Quarterly re-scan, REST API	Longitudinal studies, live dashboards

Contact: research@monitorworkspace.com — Free demo at monitorworkspace.com/scorecard

Citation: Lokentra Research Team (2026). Illinois K-12 Email Security Intelligence: DNS Authentication Profiling of 1035 School District LEAs. Lokentra U.S. Email Security Index (ESI) — State Intelligence Series. https://lokentra-site.web.app/research/states/il-k12-paper.html

Data sources: NCES Common Core of Data (CCD) 2024-2025; DNS records resolved via Google Public DNS (8.8.8.8) and Cloudflare (1.1.1.1). All entity data derived from publicly accessible government registries.

National baseline figures from Lokentra U.S. Education Sector Email Security Intelligence Dataset (March 2026). See education-dataset-paper.html for full methodology.

Illinois K-12 Email Security Intelligence:DNS Authentication Profiling of 1035 School District LEAs