{"schema_version":"secwatch.filing_event.v1","accession":"0001437749-25-019008","form_type":"8-K","ticker":"MNSB","cik":"0001693577","company_name":"MainStreet Bancshares, Inc.","filed_at":"2025-05-30T23:59:59+00:00","discovered_at":"2026-05-14T18:02:49.371825+00:00","generated_at":"2026-05-20T04:32:12.065072+00:00","sec_items":["8.01"],"event_type":"cyber","sentiment":"negative","materiality_score":0.35,"calibrated_materiality_score":0.35,"confidence":"high","headline":"MainStreet Bancshares discloses data security incident via third-party vendor affecting 4.65% of customers","bullets":["Incident discovered in March 2025 when an outside vendor to the core bank was compromised.","Company's own IT systems were not compromised; no unauthorized transactions or fund transfers occurred.","On April 28, 2025, vendor's compromised system was found to include PII on ~4.65% of customers.","Regulators notified; affected customers notified on May 26, 2025, with monitoring tools provided.","Company states incident has not materially impacted operations, financial condition, or reputation."],"urls":{"canonical":"https://secwatch.observer/filing/0001437749-25-019008","json":"https://secwatch.observer/filing/0001437749-25-019008.json","markdown":"https://secwatch.observer/filing/0001437749-25-019008.md","text":"https://secwatch.observer/filing/0001437749-25-019008.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1693577/000143774925019008/0001437749-25-019008-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1693577/000143774925019008/main20250328_8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-05-20T04:32:12.065072+00:00"},"review":{"review_status":"machine_generated","human_reviewed":false,"corrected":false,"correction_note":null,"correction_timestamp":null,"superseded_by":null,"related_filings":[]},"source_grounded_claims":[],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}