CB Financial Services, Inc.

Item 1.05. Material Cybersecurity Incidents On May 5, 2026, Community Bank (the “Bank”), the wholly-owned subsidiary of CB Financial Services, Inc. (the “Company”), became aware of an internal incident involving the handling of certain non‑public customer information using an unauthorized artificial intelligence-based software application. Upon discovery, the Bank promptly took steps to secure the information at issue and initiated an internal investigation with the assistance of external cybersecurity advisors. The investigation into the incident, including the scope and root cause, remains ongoing. The incident did not involve a disruption to the Bank's operations, customer access to accounts or services, payment systems, or core information technology infrastructure; however, due to the volume and sensitive nature of the non-public information at issue, on May 7, 2026, the Company determined the event to be material. Among the customer information the Bank has determined was disclosed are customer names, social security numbers and dates of birth. The Company is evaluating the customer data that was affected and is conducting notifications as required by applicable federal and state laws and regulatory guidance. The Company has been, and continues to be, in communication with relevant banking and financial regulators regarding the incident. The Company has taken, and continues to take, actions designed to contain and remediate the incident. The Company remains committed to protecting its customers' data and is taking measures designed to prevent future similar incidents, including but not limited to, strengthening existing controls, implementing additional controls and enhancing monitoring measures. As of the date of this disclosure, this incident has not had, and is