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                                 May 6, 2003



DigitalNet Holdings, Inc.
2525 Network Place
Herndon, VA 20171

Ladies and Gentlemen:

         We have acted as special counsel for DigitalNet Holdings, Inc., a
Delaware corporation (the "Company"), in connection with the Company's
registration statement on Form S-1 (File No. 333-102731) filed on January 27,
2003, as amended through the date hereof (the "Registration Statement") filed
with the Securities and Exchange Commission under the Securities Act of 1933,
as amended (the "Act"). The Registration Statement covers the underwritten
public offering of 6,250,000 shares of the Company's common stock, par value
$0.001 per share (the "Shares") and an over-allotment option of up to 937,500
shares of the Company's common stock, par value $0.001 per share (the
"Additional Shares").

         With your permission, all assumptions and statements of reliance herein
have been made without any independent investigation or verification on our part
except to the extent otherwise expressly stated, and we express no opinion with
respect to the subject matter or accuracy of such assumptions or items relied
upon.

         In connection with this opinion, we have (i) investigated such
questions of law, (ii) examined originals or certified, conformed or
reproduction copies of such agreements, instruments, documents and records of
the Company, such certificates of public officials and such other documents, and
(iii) received such information from officers and representatives of the Company
as we have deemed necessary or appropriate for the purposes of this opinion. In
all such examinations, we have assumed the legal capacity of all natural
persons, the genuineness of all signatures, the authenticity of original and
certified documents and the conformity to original or certified documents of all
copies submitted to us as conformed or reproduction copies. As to various
questions of fact relevant to the opinions expressed herein, we have relied
upon, and assume the accuracy of, representations and warranties contained in
the documents and certificates and oral or written statements and other
information of or from representatives of the Company and others and assume
compliance on the part of all parties to the documents with their covenants and
agreements contained therein.


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DigitalNet Holdings, Inc.
May 6, 2003


         Based upon the foregoing, and subject to the limitations,
qualifications and assumptions set forth herein, we are of the opinion that (i)
the Shares, when issued, delivered and paid for as contemplated by the
Registration Statement, will be validly issued, fully paid and non-assessable
and (ii) the Additional Shares, when issued, delivered and paid for as
contemplated by the Registration Statement, will be validly issued, fully paid
and non-assessable.

         The opinions expressed herein are limited to the General Corporation
Law of the State of Delaware, the Delaware Constitution and reported judicial
decisions interpreting those laws, each as currently in effect. We assume no
obligation to supplement this letter if any applicable laws change after the
date hereof or if we become aware of any facts that might change the opinion
expressed herein after the date hereof.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to this firm under the caption
"Legal Matters" in the Registration Statement. In giving this consent, we do not
hereby admit that we are in the category of persons whose consent is required
under Section 7 of the Act.



                                                    Very truly yours,

                                        FRIED, FRANK, HARRIS, SHRIVER & JACOBSON



                                        By: /s/ Lawrence R. Bard
                                           -------------------------
                                                Lawrence R. Bard