Cel Sci Corp — 8-K exhibit

EXHIBIT 5.1

HART & HART, LLC

ATTORNEYS AT LAW

1624 Washington Street

Denver, CO 80203

June 16, 2026

CEL-SCI Corporation

8229 Boone Blvd. #802

Vienna, VA 22182

This letter will constitute our opinion regarding the legality of the issuance by CEL-SCI Corporation, a Colorado corporation (“CEL-SCI”) of 2,500,000 shares of its common stock (the “Shares”) as referred to in the Registration Statement on Form S-3 (File No. 333-288515) (the “Registration Statement”) filed with the Securities and Exchange Commission, declared effective by the Securities and Exchange Commission (the “Commission”) on August 12, 2025, the prospectus included therein (the “Prospectus”) and the prospectus supplement, dated June 14, 2026 (the “Prospectus Supplement”). The Prospectus Supplement pertains to a best efforts offering pursuant to a Placement Agency Agreement dated June 14, 2026 between the Company and ThinkEquity, LLC (“Placement Agency Agreement”).

We have examined the Articles of Incorporation, the Bylaws and the minutes of the Board of Directors of CEL-SCI, the applicable laws of the State of Colorado, and a copy of the Registration Statement, the Prospectus and the Prospectus Supplement. In our opinion:

We hereby consent to the filing of this opinion letter as an exhibit to the Company’s Current Report on Form 8-K and to the reference to this firm in the Prospectus under the caption “Legal Matters.” In giving our consent, we do not hereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.