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Exhibit 10.12

SECURITY AND PLEDGE AGREEMENT

        SECURITY AND PLEDGE AGREEMENT, dated as of September 19, 2001 (the
"Agreement"), by and between Douglas A. Sabella (the "Pledgor"), and Tumbleweed
Communications Corp., a Delaware corporation (the "Pledgee").

        WHEREAS, in consideration for the Pledgee's loan of Two Hundred and
Fifty Thousand Dollars ($250,000.00) to the Pledgor, the Pledgor is delivering
to the Pledgee a duly executed promissory note, dated the date hereof (such note
as it may be amended, modified or supplemented from time to time together with
any replacement thereof, the "Note"), in the principal amount of Two Hundred and
Fifty Thousand Dollars ($250,000.00) in favor of the Pledgee; and

        WHEREAS, the Pledgor has agreed to pledge the Pledged Securities (as
defined below) and the Proceeds (as defined below) to the Pledgee to secure the
Pledgor's obligations under the Note.

        NOW, THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

        1.    Grant of Security Interest in Collateral.    The Pledgor hereby
grants to the Pledgee, as security for all present and future obligations and
liabilities of all kinds of the Pledgor to the Pledgee under the Note and this
Agreement (collectively referred to as the "Obligations"), a first priority
security interest in the following described property (collectively referred to
as the "Collateral"):

        (a)  Except for the 13,888 shares of Pledgee common stock issued to
Pledgor in connection with that certain Restricted Stock Agreement dated June 4,
2001 by and between Pledgee and Pledgor, any and all fully paid and
nonassessable shares of Pledgee capital stock issued by the Pledgee to the
Pledgor including, without limitation, shares of Pledgee common stock issued
pursuant to the exercise of stock options to purchase Pledgee common stock (the
"Pledged Capital Stock"); and

        (b)  any and all stock options issued by the Pledgor to the Pledgee to
purchase shares of Pledgee common stock (the "Pledged Options" and collectively
with the Pledged Capital Stock, the "Pledged Securities"); and

        (c)  the certificates, option grants, and any other such documents
representing the Pledged Securities and all of the Pledgor's rights and
privileges with respect thereto; and

        (d)  the proceeds and accessions of the Pledged Securities (the
"Proceeds").

        2.    Pledgor's Covenants.    

        (a)  The Pledgor agrees (i) hereafter not to encumber or grant a
security interest in or a lien or other encumbrance on the Collateral, and
(ii) not to dispose of any of the Collateral except in accordance with the terms
of this Agreement.

        (b)  The Pledgor agrees: (i) at any time and from time to time, upon
request of the Pledgee, to give, execute, file and/or record any notice,
financing statement, continuation statement, instrument, document or agreement
that the Pledgee shall consider reasonably necessary or desirable to create,
preserve, continue, perfect or validate any security interest granted hereunder
or which the Pledgee may consider reasonably necessary or desirable to exercise
or enforce its rights hereunder with respect to such security interest; and
(ii) to do other acts or things necessary to keep the Collateral and the
Proceeds free and clear of all defenses, rights of offset and counterclaim.

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        (c)  The Pledgor agrees to: (i) pay promptly the Obligations secured
hereby when due; and (ii) indemnify the Pledgee against all loss, claims,
demands and liabilities of every kind arising from the Collateral and the
transactions and other agreements and undertakings contemplated hereby.

        3.    Payment of Taxes, Charges, Liens and Assessments.    The Pledgor
agrees to pay, prior to delinquency, all taxes, charges, liens and assessments
against the Collateral and the Proceeds, and upon the failure of the Pledgor to
do so, the Pledgee, at its option, may pay any of them. Any such payments made
by the Pledgee shall be obligations of the Pledgor to the Pledgee, due and
payable immediately without demand and shall be secured by the Collateral and
the Proceeds, subject to all of the terms and conditions of this Agreement.

        4.    Powers of Pledgee.    The Pledgor appoints the Pledgee his true
attorney in fact to perform any of the following powers, which are coupled with
an interest, are irrevocable until termination of this Agreement and may be
exercised from time to time by the Pledgee's officers and employees, or any of
them, whether or not the Pledgor is in default: (a) to perform any obligations
of the Pledgor hereunder in the Pledgor's name or otherwise; (b) to give notice
of Pledgee's right under the Collateral to enforce the same; (c) to release
security; (d) to resort to security; (e) to prepare, execute, file, record or
deliver notes, assignments, schedules, designation statements, financing
statements, continuation statements, termination statements, statements of
assignment, applications for registration or like papers to perfect, preserve or
release the Pledgee's interest in the Collateral; (f) after an Event of Default,
to endorse, collect, deliver and receive payment under instruments for the
payment of money constituting or relating to the Collateral; (g) after an Event
of Default, to preserve or release the interest evidenced by chattel paper to
which the Pledgee is entitled hereunder and to endorse and deliver evidences of
title incidental thereto; (h) after an Event of Default, to exercise all rights,
powers and remedies which the Pledgor would have, but for this Agreement, under
all Collateral subject to this Agreement; and (i) to do all acts and things and
execute all documents in the name of the Pledgor otherwise, deemed by the
Pledgee as necessary, proper and convenient in connection with the preservation,
perfection or enforcement of its rights hereunder.

        5.    Events of Default; Remedies.    

        (a)  Each of the following shall constitute an event of default ("Event
of Default") hereunder: (i) the Pledgor's failure to pay, within fifteen
(15) days after the date when such payment is due, any payment of principal or
interest on the Note; or (ii) the Pledgor's failure to observe or perform any
covenant or agreement contained in the Note; and (iii) the Pledgor's violation
of any of the transfer restrictions that may be contained in any restrictive
legend contained in Pledgee securities issued to the Borrower.

        (b)  In case an Event of Default shall have occurred and be continuing,
the Pledgee shall be entitled to exercise all of the rights, powers and remedies
(whether vested in it by this Agreement, the Note or by law and including,
without limitation, all rights and remedies of a secured party of a debtor in
default under the Uniform Commercial Code as in force in the State of
California) for the protection and enforcement of its rights in respect of the
Collateral. In addition to recourse against the Collateral as provided in this
Agreement, the Pledgee shall be entitled to recourse against the Pledgor for the
payment of any principal or interest on the Note or for any claim based thereon
(including costs of collection).

        6.    No Waiver.    The failure of the Pledgee to exercise any right or
remedy under this Agreement or the Note, or delay by the Pledgee in exercising
same, will not operate as a waiver thereof. No waiver by the Pledgee will be
effective unless and until it is in writing and signed by the Pledgee. No waiver
of any condition or performance will operate as a waiver of any subsequent
condition or obligation. The Pledgee shall have no obligation to resort to the
Collateral or any other security which is or may become available to it.

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        7.    Consents to Sales of Pledged Capital Stock.    In the event that
the value of the Pledged Capital Stock exceeds the value of the Obligations, and
Pledgor desires to sell some or all of that portion of the Pledged Capital Stock
which exceeds the value of the Obligations, Pledgor will petition the Board of
Directors of the Pledgee for its consent to permit such sale, which consent
shall not unreasonably be withheld.

        8.    Miscellaneous.    

        (a)  This Agreement, any amendments or replacement hereof, and the
legality, validity and performance of the terms hereof, shall be governed by and
enforced and construed in accordance with the laws of the State of California
without regard to conflicts of laws and principles thereof.

        (b)  This Agreement and the rights, powers and duties set forth herein
shall be binding upon the Pledgor, its agents, representatives and successors
and shall inure to the benefit of the Pledgee and its successors and assigns
and, in the event of any transfer or assignment of rights by the Pledgee, the
rights and privileges herein conferred upon the Pledgee shall automatically
extend to and be vested in such transferee or assignee, all subject to the terms
and conditions hereof. This Agreement and the rights and privileges herein
conferred upon the Pledgee may be assigned by the Pledgee without the consent of
the Pledgor. This Agreement may not be transferred or assigned by the Pledgor
without the written consent of the Pledgee.

        (c)  In the event that any provision of this Agreement is invalid or
unenforceable under any applicable statute or rule of law, then such provision
shall be deemed inoperative to the extent that it may conflict therewith and
shall be modified to conform with such statute or rule of law. Any provision
hereof which may prove invalid or unenforceable under any applicable law shall
not effect the validity or enforceability of any other provisions hereof.

        (d)  Notices required or permitted to be given under this Agreement
shall be in writing and may be delivered personally or sent to a party by
airmail or first class mail, postage prepaid and addressed to such party, as
follows, or to such other address furnished by notice given in accordance with
this paragraph:

If to the Pledgor:
Douglas A. Sabella
21771 Congress Hall Lane
Saratoga, CA 95070

If to the Pledgee:
Tumbleweed Communications Corp.
700 Saginaw Drive
Redwood City, California 94063
Attention:    Chief Financial Officer

Any such notice shall be deemed to have been given, (i) if sent by mail, five
(5) days after the date mailed, and (ii) if delivered personally, on the date of
delivery.

        (e)  This Agreement may be executed in one or more counterparts, each of
which shall be deemed an original but all of which shall together constitute one
and the same document.

        (f)    This Agreement and the security interest and pledge hereunder
shall terminate upon the full and final performance of all Obligations of the
Pledgor and payment of all indebtedness secured hereby. At such time, the
Pledgee shall promptly reassign to the Pledgor all of the Collateral hereunder
which has not been sold, disposed of, retained or applied by the Pledgee in
accordance with the terms hereof.

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        IN WITNESS WHEREOF, the undersigned have caused this Agreement to be
executed as of the date first written above.

Date:    September 19, 2001 PLEDGOR:

 
/s/  DOUGLAS A. SABELLA      

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Douglas A. Sabella
Director, President and
Chief Operating Officer

    PLEDGEE:
 
 
Tumbleweed Communications Corp.
 
 
By:
/s/  JEFFREY C. SMITH      

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Name:    Jeffrey C. Smith
Title:      Chairman and Chief Executive Officer

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Exhibit 10.12

SECURITY AND PLEDGE AGREEMENT