Exhibit 24

                                POWER OF ATTORNEY

     The undersigned, as a Section 16 reporting person of Barracuda Networks,
Inc. (the "Company"), hereby constitutes and appoints David Faugno and Diane C.
Honda, the undersigned's true and lawful attorney-in-fact to:

     1.   prepare, execute in the undersigned's name and on the undersigned's
          behalf, and submit to the Securities and Exchange Commission (the
          "SEC") a Form ID, including amendments thereto, and any other
          documents necessary or appropriate to obtain EDGAR codes and passwords
          enabling the undersigned to make electronic filings with the SEC of
          reports required by Section 16(a) of the Securities Exchange Act of
          1934 or any rule or regulation of the SEC;

     2.   complete and execute Forms 3, 4 and 5 and other forms and all
          amendments thereto as such attorney-in-fact shall in his discretion
          determine to be required or advisable pursuant to Section 16 of the
          Securities Exchange Act of 1934 (as amended) and the rules and
          regulations promulgated thereunder, or any successor laws and
          regulations, as a consequence of the undersigned's ownership,
          acquisition or disposition of securities of the Company; and

     3.   do all acts necessary in order to file such forms with the SEC, any
          securities exchange or national association, the Company and such
          other person or agency as the attorney-in-fact shall deem appropriate.

     The undersigned hereby ratifies and confirms all that said attorney-in-fact
and agent shall do or cause to be done by virtue hereof. The undersigned
acknowledges that the foregoing attorney-in-fact, in serving in such capacity at
the request of the undersigned, is not assuming, nor is the Company assuming,
any of the undersigned's responsibilities to comply with Section 16 of the
Securities Exchange Act of 1934 (as amended).

     This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4 and 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier revoked by the undersigned in a signed writing delivered to the
Company and the foregoing attorney-in-fact.

     IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 23rd day of October, 2013.

                                        Signature: /s/ Zachary S. Levow
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                                        Print Name: Zachary S. Levow
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