<PAGE>   1
                               WARRANT CERTIFICATE


        THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
        ACT OF 1933, AS AMENDED (THE "SECURITIES ACT") OR UNDER THE
        SECURITIES LAWS OF ANY JURISDICTION AND MAY NOT BE
        TRANSFERRED, SOLD OR OTHERWISE DISPOSED OF UNLESS A
        REGISTRATION STATEMENT IS IN EFFECT UNDER THE SECURITIES ACT
        AND ANY APPLICABLE SECURITIES LAWS WITH RESPECT TO SUCH
        SECURITIES OR A WRITTEN OPINION OF COUNSEL REASONABLY
        ACCEPTABLE TO THE COMPANY IS PROVIDED TO THE COMPANY TO THE
        EFFECT THAT NO REGISTRATIONS ARE REQUIRED UNDER SUCH
        SECURITIES LAWS.


Warrant No. 1                                                   358,423 Warrants
                                                          (Subject to Adjustment
                                                             as Provided Herein)

                            SOFTWARE.NET CORPORATION

                               WARRANT CERTIFICATE


     This warrant certificate ("Warrant Certificate") certifies that for value
received AMERICA ONLINE, INC., 22000 AOL Way, Dulles, Virginia 20166, or its
registered assigns (the "Holder") is the owner of the number of warrants
("Warrants") specified above, each of which entitles the Holder thereof to
purchase one fully paid and non-assessable share of Common Stock, no par value
("Common Stock"), of software.net Corporation, a Delaware corporation (fomerly
CyberSource Corporation, a California corporation) (the "Company"), at a
purchase price of $8.37 per share of Common Stock in lawful money of the United
States of America in cash or by certified or cashier's check or a combination of
cash and certified or cashier's check (subject to adjustment as hereinafter
provided).

     1.   Warrant; Purchase Price. Each Warrant shall entitle the Holder
initially to purchase one share of Common Stock of the Company and the purchase
price payable upon exercise of the Warrants shall initially be $8.37 per share
of Common Stock (the "Purchase Price"). The Purchase Price and number of shares
of Common Stock issuable upon exercise of each Warrant are subject to adjustment
as provided in Article 6. The shares of Common Stock issuable upon exercise of
the Warrants (and/or other shares of Common Stock so issuable by reason of any
adjustments pursuant to Article 6) are sometimes referred to herein as the
"Warrant Shares." 

<PAGE>   2


     2.   Exercise; Expiration Date.

          2.1. The Warrants are exercisable, at the option of the Holder, in
whole or in part at any time and from time to time in an amount up to 9,956
Warrants for each full month following March 1, 1998 and ending, in each case,
on the Expiration Date, upon surrender of this Warrant Certificate to the
Company together with a duly completed Notice of Exercise, in the form attached
hereto as Exhibit A, and payment of an amount equal to the Purchase Price times
the number of Warrants to be exercised. In the case of exercise of less than all
the Warrants represented by this Warrant Certificate, the Company shall cancel
the Warrant Certificate upon the surrender thereof and shall execute and deliver
a new Warrant Certificate for the balance of such Warrants. Notwithstanding the
foregoing provisions of this Section 2.1, in the event of a Change of Control
(as hereafter defined), any outstanding Warrants granted hereunder that are not
then exercisable, in accordance with the vesting provisions set forth in this
Section 2.1, shall become immediately exercisable. For purposes of this Section
2.1, a Change of Control shall mean (i) at such time as any person (other than
existing shareholders of the Company) obtains the right to designate a majority
of the members of the Company's Board of Directors or acquires sufficient shares
of the Company's outstanding voting stock to cause the election of a majority of
the seats on the Company's Board of Directors, (ii) the Company merges with
another entity and the Company's stockholders prior to the merger do not retain
control of the combined entity, or (iii) the Company sells substantially all of
its assets or capital stock. 

          2.2. The term "Expiration Date" shall mean 5:00 p.m. California time
on March 1, 2005 or if such day shall in the State of California be a holiday or
a day on which banks are authorized to close, then 5:00 p.m. California time the
next following day which in the State of California is not a holiday or a day on
which banks are authorized to close. 

     3.   Registration and Transfer on Company Books. 

          3.1. The Company shall maintain books for the registration and 
transfer of the Warrants and the registration and transfer of the Warrant
Shares. 

          3.2. Prior to due presentment for registration of transfer of this 
Warrant Certificate, or the Warrant Shares, the Company may deem and treat the
registered Holder as the absolute owner thereof.

     4.   Reservation of Shares. The Company covenants that it will at all times
reserve and keep available out of its authorized capital stock, solely for the
purpose of issue upon exercise of the Warrants, such number of shares of capital
stock as shall then be issuable upon the exercise or exchange of all outstanding
Warrants and upon conversion of shares issuable upon exercise of such Warrants.
The Company covenants that all shares of capital stock which shall be issuable
upon exercise of the Warrants shall be duly and validly issued and fully paid
and non-assessable and free from all taxes, liens and charges with respect to
the issue thereof, and that upon issuance such shares shall be listed on each
national securities exchange, if any, or the Nasdaq National Market on which the
other shares of such outstanding capital stock of the Company are then listed or
traded.

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<PAGE>   3

     5.   Loss or Mutilation. Upon receipt by the Company of reasonable evidence
of the ownership of and the loss, theft, destruction or mutilation of any
Warrant Certificate and, in the case of loss, theft or destruction, of indemnity
reasonably satisfactory to the Company (provided that if Holder is an
institutional investor or a nominee of an institutional investor, such
institutional investor's own unsecured agreement of indemnity shall be deemed to
be satisfactory for such purpose), or, in the case of mutilation, upon surrender
and cancellation of the mutilated Warrant Certificate, the Company shall execute
and deliver in lieu thereof a new Warrant Certificate representing an equal
number of Warrants. 

     6.   Adjustment of Purchase Price and Number of Shares Deliverable. 

          6.1. The number of Warrant Shares purchasable upon the exercise of
each Warrant and the Purchase Price with respect to the Warrant Shares shall be
subject to adjustment as follows:

               (a)  In case the Company shall (i) declare a dividend or make a
distribution on its Common Stock payable in shares of its capital stock, (ii)
subdivide its outstanding shares of Common Stock through stock split or
otherwise, (iii) combine its outstanding shares of Common Stock into a smaller
number of shares of Common Stock, or (iv) issue by reclassification of its
Common Stock (including any reclassification in connection with a consolidation
or merger in which the Company is the continuing corporation) other securities
of the Company, the number and/or nature of Warrant Shares purchasable upon
exercise of each Warrant immediately prior thereto shall be adjusted so that the
Holder shall be entitled to receive the kind and number of Warrant Shares or
other securities of the Company which it would have owned or have been entitled
to receive after the happening of any of the events described above, had such
Warrant been exercised immediately prior to the happening of such event or any
record date with respect thereto. Any adjustment made pursuant to this paragraph
(a) shall become effective retroactively as of the record date of such event.

               (b)  In case the Company shall issue rights, options or warrants
or securities convertible into or exercisable or exchangeable directly or
indirectly into Common Stock to all holders of its shares of Common Stock ,
entitling them to subscribe for or purchase shares of Common Stock at a price
per share which (together with the value of the consideration, if any, payable
for such rights, options, warrants or convertible securities) is lower on the
record date referred to below than the then Market Price Per Share of such
Common Stock (as determined pursuant to Section 9.2) the number of Warrant
Shares thereafter purchasable upon the exercise of each Warrant shall be
determined by multiplying the number of Warrant Shares immediately theretofore
purchasable upon exercise of each Warrant by a fraction, of which the numerator
shall be the number of shares of Common Stock outstanding on such record date
plus the number of additional shares of Common Stock offered for subscription or
purchase, and of which the denominator shall be the number of shares of Common
Stock outstanding on such record date plus the number of shares which the
aggregate offering price of the total number of shares of Common Stock so
offered would purchase at the then Market Price Per Share of such Common Stock.
Such adjustment shall be made whenever such rights, options, warrants or
convertible securities are issued, and shall become effective retroactively as
of the record date for


                                      -3-

<PAGE>   4

the determination of shareholders entitled to receive such rights, options,
warrants or convertible securities. In the case such subscription price may be
paid in consideration, part of which or all which is in a form other than cash,
the value of such consideration shall be determined in good faith by the Board
of Directors of the Company.

               (c)  In case the Company shall distribute to all holders of its
shares of Common Stock, or all holders of Common Stock shall otherwise become
entitled to receive, shares of capital stock of the Company (other than
dividends or distributions on its Common Stock referred to in paragraph (a)
above), evidences of its indebtedness or rights, options, warrants or
convertible securities providing the right to subscribe for or purchase any
shares of the Company's capital stock or evidences of its indebtedness (other
than any rights, options, warrants or convertible securities referred to in
paragraph (b) above), then in each case the number of Warrant Shares thereafter
purchasable upon the exercise of each Warrant shall be determined by multiplying
the number of Warrant Shares theretofore purchasable upon the exercise of each
Warrant, by a fraction, of which the numerator shall be the then Market Price
Per Share of the Warrant Shares (as determined pursuant to Section 9.2) on the
record date mentioned below in this paragraph (c), and of which the denominator
shall be the then Market Price Per Share of the Warrant Shares on such record
date, less the then fair value (as determined by the Board of Directors of the
Company, in good faith) of the portion of the shares of the Company's capital
stock other than Common Stock, evidences of indebtedness, or of such rights,
options, warrants or convertible securities, distributable with respect to each
Warrant Share. Such adjustment shall be made whenever any such distribution is
made, and shall become effective retroactively as of the record date for the
determination of shareholders entitled to receive such distribution. 

               (d)  In the event of any capital reorganization or any
reclassification of the capital stock of the Company or in case of the
consolidation or merger of the Company with another corporation (other than a
consolidation or merger in which the outstanding shares of the Company's Common
Stock are not converted into or exchanged for other rights or interests), or in
the case of any sale, transfer or other disposition to another corporation of
all or substantially all the properties and assets of the Company, the Holder of
each Warrant shall thereafter be entitled to purchase (and it shall be a
condition to the consummation of any such reorganization, reclassification,
consolidation, merger, sale, transfer or other disposition that appropriate
provisions shall be made so that such Holder shall thereafter be entitled to
purchase) the kind and amount of shares of stock and other securities and
property (including cash) which the Holder would have been entitled to receive
had such Warrants been exercised immediately prior to the effective date of such
reorganization, reclassification, consolidation, merger, sale, transfer or other
disposition; and in any such case appropriate adjustments shall be made in the
application of the provisions of this Article 6 with respect to rights and
interest thereafter of the Holder of the Warrants to the end that the provisions
of this Article 6 shall thereafter be applicable, as near as reasonably may be,
in relation to any shares or other property thereafter purchasable upon the
exercise of the Warrants. The provisions of this Section 6.1(d) shall similarly
apply to successive reorganizations, reclassifications, consolidations, mergers,
sales, transfers or other dispositions.


                                      -4-
 
<PAGE>   5

               (e)  Whenever the number of Warrant Shares purchasable upon the
exercise of each Warrant is adjusted, as provided in this Section 6.1, the
Purchase Price with respect to the Warrant Shares shall be accordingly adjusted
in order to reflect the number of Warrant Shares then and thereafter issuable.


          6.2. In the event the Company shall declare a dividend, or make a
distribution to the holders of its Series D Preferred generally, whether in
cash, property or assets of any kind, including any dividend payable in stock or
securities of any other issuer owned by the Company (excluding any dividend or
distribution referred to in Section 6.1(a) or (c) above), the Purchase Price of
each Warrant shall be reduced, without any further action by the parties hereto,
by the Per Share Value (as hereinafter defined) of the dividend. For purposes of
this Section 6.2, the "Per Share Value" of a cash dividend or other distribution
shall be the dollar amount of the distribution on each share of Series D
Preferred and the "Per Share Value" of any dividend or distribution other than
cash shall be equal to the fair market value of such non-cash distribution on
each share of Series D Preferred as determined in good faith by the Board of
Directors of the Company.

          6.3. No adjustment in the number of Warrant Shares purchasable under
the Warrants, or in the Purchase Price with respect to the Warrant Shares, shall
be required unless such adjustment would require an increase or decrease of at
least 1% in the number of Warrant Shares issuable upon the exercise of such
Warrant, or in the Purchase Price thereof; provided, however, that any
adjustments which by reason of this Section 6.3 are not required to be made
shall be carried forward and taken into account in any subsequent adjustment.
All final results of adjustments to the number of Warrant Shares and the
Purchase Price thereof shall be rounded to the nearest share or the nearest
cent, as the case may be. Anything in this Section 6 to the contrary
notwithstanding, the Company shall be entitled, but shall not be required, to
make such changes in the number of Warrant Shares purchasable upon the exercise
of each Warrant, or in the Purchase Price thereof, in addition to those required
by such Section, as it in its discretion shall determine to be advisable in
order that any dividend or distribution in shares of Common Stock, subdivision,
reclassification or combination of shares of Common Stock, issuance of rights,
warrants or options to purchase Common Stock, or distribution of shares of stock
other than Common Stock, evidences of indebtedness or assets (other than
distributions of cash out of retained earnings) or convertible or exchangeable
securities hereafter made by the Company to the holders of its Common Stock
shall not result in any tax to the holders of its Common Stock or securities
convertible into Common Stock.

          6.4. Whenever the number of Warrant Shares purchasable upon the
exercise of each Warrant or the Purchase Price of such Warrant Shares is
adjusted, as herein provided, the Company shall mail to the Holder, at the
address of the Holder shown on the books of the Company, a notice of such
adjustment or adjustments, prepared and signed by the Chief Financial Officer or
Secretary of the Company, which sets forth the number of Warrant Shares
purchasable upon the exercise of each Warrant and the Purchase Price of such
Warrant Shares after such adjustment, a brief statement of the facts requiring
such adjustment and the computation by which such adjustment was made.


                                      -5-

<PAGE>   6

          6.5. In the event that at any time prior to the expiration of the
Warrants and prior to their exercise:

               (a)  the Company shall declare any distribution (other than a
cash dividend or a dividend payable in securities of the Company with respect to
the Common Stock); or 

               (b)  the Company shall offer for subscription to the holders of
the Common Stock (as a class) any additional shares of stock of any class or any
other securities convertible into Common Stock or any rights to subscribe
thereto; or

               (c)  the Company shall declare any stock split, stock dividend,
subdivision, combination, or similar distribution with respect to the Common
Stock, regardless of the effect of any such event on the outstanding number of
shares of Common Stock; or

               (d)  the Company shall declare a dividend, other than a dividend
payable in shares of the Company's own Common Stock; or

               (e)  there shall be any capital change in the Company as set
forth in Section 6.1(d); or

               (f)  there shall be a voluntary or involuntary dissolution,
liquidation, or winding up of the Company (other than in connection with a
consolidation, merger, or sale of all or substantially all of its property,
assets and business as an entity); (each such event hereinafter being referred
to as a "Notification Event"); or

the Company shall cause to be mailed to the Holder, not less than 20 days prior
to the record date, if any, in connection with such Notification Event
(provided, however, that if there is no record date, or if 20 days prior notice
is impracticable, as soon as practicable) written notice specifying the nature
of such event and the effective date of, or the date on which the books of the
Company shall close or a record shall be taken with respect to, such event. Such
notice shall also set forth facts indicating the effect of such action (to the
extent such effect may be known at the date of such notice) on the Purchase
Price and the kind and amount of the shares of stock or other securities or
property deliverable upon exercise of the Warrants.

          6.6. The form of Warrant Certificate need not be changed because of
any change in the Purchase Price, the number of Warrant Shares issuable upon the
exercise of a Warrant or the number of Warrants outstanding pursuant to this
Section 6, and Warrant Certificates issued before or after such change may state
the same Purchase Price, the same number of Warrants, and the same number of
Warrant Shares issuable upon exercise of Warrants as are stated in the Warrant
Certificates theretofore issued pursuant to this Agreement. The Company may,
however, at any time, in its sole discretion, make any change in the form of
Warrant Certificate that it may deem appropriate and that does not affect the
substance thereof, and any Warrant Certificates thereafter issued or
countersigned, whether in exchange or substitution for an outstanding Warrant
Certificate or otherwise, may be in the form as so changed.

                                      -6-

<PAGE>   7


     7.   Conversion Rights.

          7.1. In lieu of exercising of any portion of the Warrants as provided
in Section 2.1 hereof, the Warrants represented by this Warrant Certificate (or
any portion thereof) may, at the election of the Holder, be converted into the
nearest whole number of shares of Common Stock equal to: (1) the product of (a)
the number of shares of Common Stock then issuable upon the exercise of each
Warrant multiplied by (b) the excess, if any, of (i) the Market Price Per Share
(as determined pursuant to Section 9.2) with respect to the date of conversion
over (ii) the Purchase Price in effect on the business day next preceding the
date of conversion, divided by (2) the Market Price Per Share with respect to
the date of conversion.

          7.2. The conversion rights provided under this Section 7 may be
exercised in whole or in part and at any time and from time to time while any
Warrants remain outstanding, provided that they are at the time currently
exercisable. In order to exercise the conversion privilege, the Holder shall
surrender to the Company, at its offices, this Warrant Certificate accompanied
by a duly completed Notice of Conversion in the form attached hereto as Exhibit
B. The Warrants (or so much thereof as shall have been surrendered for
conversion) shall be deemed to have been converted immediately prior to the
close of business on the day of surrender of such Warrant Certificate for
conversion in accordance with the foregoing provisions. As promptly as
practicable on or after the conversion date, the Company shall issue and shall
deliver to the Holder (i) a certificate or certificates representing the number
of shares of Common Stock to which the Holder shall be entitled as a result of
the conversion, and (ii) if the Warrant Certificate is being converted in part
only, a new certificate of like tenor and date for the balance of the
unconverted portion of the Warrant Certificate.

     8.   Voluntary Adjustment by the Company. The Company may, at its option, 
at any time during the term of the Warrants, reduce the then current Purchase
Price to any amount deemed appropriate by the Board of Directors of the Company
and/or extend the date of the expiration of the Warrants.

     9.   Fractional Shares and Warrants; Determination of Market Price Per 
Share.

          9.1. Anything contained herein to the contrary notwithstanding, the
Company shall not be required to issue any fraction of a share of Common Stock
in connection with the exercise of Warrants. Warrants may not be exercised in
such number as would result (except for the provisions of this paragraph) in the
issuance of a fraction of a share of Common Stock unless the Holder is
exercising all Warrants then owned by the Holder. In such event, the Company
shall, upon the exercise of all of such Warrants, issue to the Holder the
largest aggregate whole number of shares of Common Stock called for thereby upon
receipt of the Purchase Price for all of such Warrants and pay a sum in cash
equal to the remaining fraction of a share of Common Stock, multiplied by its
Market Price Per Share (as determined pursuant to Section 9.2 below) as of the
last business day preceding the date on which the Warrants are presented for
exercise.

          9.2. As used herein, the "Market Price Per Share" with respect to any
class or series of Common Stock on any date shall mean the average closing price
per share of the Company's Common Stock for the five trading days immediately
preceding such date. The

                                      -7-

<PAGE>   8


closing price for each such day shall be the last sale price regular way or, in
case no such sale takes place on such day, the average of the closing bid and
asked prices regular way, in either case on the principal securities exchange on
which the shares of such Common Stock of the Company are listed or admitted to
trading or, if applicable, the last sale price, or in case no sale takes place
on such day, the average of the closing bid and asked prices of such Common
Stock on Nasdaq National Market or any comparable system, or if such Common
Stock is not reported on Nasdaq National Market or a comparable system, the
average of the closing bid and asked prices as furnished by two members of the
National Association of Securities Dealers, Inc. selected from time to time by
the Company for that purpose. If such bid and asked prices are not available,
then "Market Price Per Share" shall be equal to the fair market value of such
Common Stock as determined in good faith by the Board of Directors of the
Company.

     10.  Registration and Information Rights. The Holder shall be entitled to
the registration rights, the special covenants of the Company relating to
certain rights to information, and other covenants contained in that certain
Registration Rights Agreement dated as of March 18, 1998, between the Holder and
the Company and Common Stock and Warrant Subscription Agreement dated as of
March 18, 1998, between the Holder and the Company (the "Subscription
Agreement").

     11.  Transferability of Warrant. THIS WARRANT CERTIFICATE AND/OR THE
WARRANTS MAY ONLY BE TRANSFERRED UPON COMPLIANCE WITH THE TERMS OF THE
SUBSCRIPTION AGREEMENT.

     12.  Amendments.

          12.1. Any term of this Warrant Certificate may be amended and the
observance of any term of the Warrant Certificate may be waived (either
generally or in a particular instance and either retroactively or
prospectively), only with the written consent of the Company and the Holder.

          12.2. No waivers of, or exceptions to, any term, condition or
provision of this Warrant Certificate, in any one or more instances, shall be
deemed to be, or construed as, a further or continuing waiver of any such term,
condition or provision.

     13.  Governing Law. This Warrant Certificate shall be governed by and
construed in accordance with the laws of the State of California.


                                      -8-
<PAGE>   9




     IN WITNESS WHEREOF, the Company has caused this Warrant Certificate to be
duly executed by its officers thereunto duly authorized and its corporate seal
to be affixed hereon, as of this 17 day of June, 1998


                                  SOFTWARE.NET CORPORATION, a 
                                  Delaware corporation.

                                  By: /s/ Mark L. Breier
                                      -----------------------------
                                  Name:    Mark L. Brier
                                  Title:   President and Chief Executive Officer





                                      -9-



<PAGE>   10




                                    EXHIBIT A


                               NOTICE OF EXERCISE


     The undersigned hereby irrevocably elects to exercise, pursuant to Section
2 of the Warrant Certificate accompanying this Notice of Exercise, _______
Warrants of the total number of Warrants owned by the undersigned pursuant to
the accompanying Warrant Certificate, and herewith makes payment of the Purchase
Price of such shares in full.



                                       By:
                                           -------------------------------------
                                       Name: 
                                             -----------------------------------
                                       Address:
                                                --------------------------------
                    
                                                --------------------------------

                                                --------------------------------





                                      -10-


<PAGE>   11




                                    EXHIBIT B


                              NOTICE OF CONVERSION


     The undersigned hereby irrevocably elects to convert, pursuant to Section 7
of the Warrant Certificate accompanying this Notice of Conversion, _________
Warrants of the total number of Warrants owned by the undersigned pursuant to
the accompanying Warrant Certificate into shares of the Common Stock of the
Company (the "Shares"). The number of Shares to be received by the undersigned
shall be calculated in accordance with the provisions of Section 7.1 of the
accompanying Warrant Certificate.


                                       By:
                                           -------------------------------------
                                       Name: 
                                             -----------------------------------
                                       Address:
                                                --------------------------------
                    
                                                --------------------------------

                                                --------------------------------




                                      -11-