TSP Fiduciary Security Act This bill incorporates national security interests into management of the Thrift Savings Fund. Specifically, the bill requires fiduciaries that are responsible for managing the fund (i.e., the Federal Retirement Thrift Investment Board) to prevent fund investments and associated votes that harm the national security of the United States, including investments in entities on certain lists maintained by the Department of Defense and the Department of Commerce (e.g., Chinese military companies). The Department of Labor must issue implementing regulations that include these and other standards for compliance. Beginning January 1, 2025, fiduciaries may be held personally liable for monetary damages and may be assessed civil penalties for failing to meet these requirements.