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                                                                    Exhibit 10.5

                      SENIOR EXECUTIVE SEVERANCE AGREEMENT


                  THIS AGREEMENT is made as of January 1, 2001 by and between
CENTRAL NATIONAL BANK, CANAJOHARIE, a national banking association located in
Canajoharie, New York (the "Bank"), CNB FINANCIAL CORP., the bank holding
company for the Bank (the "Corporation"), and PETER J. CORSO (the "Executive").

                                   WITNESSETH:

                  WHEREAS, the Board of Directors (the "Board") of the
Corporation has authorized the Corporation to enter into severance agreements
with certain key executives of the Corporation and the Bank; and

                  WHEREAS, the Executive is a key executive of the Corporation
and/or the Bank and has been selected by the Board as a key executive to be a
party to this Agreement; and

                  WHEREAS, should the Corporation receive any hostile proposal
from a third person concerning any possible business combination with, or
acquisition of equity securities of, the Corporation, the Board believes it
imperative that the Corporation and the Board be able to rely upon the Executive
to continue in his position, and that the Corporation be able to receive and
rely upon his advice, if it requests it, as to the best interests of the
Corporation and its shareholders without concern that he might be distracted by
the personal uncertainties and risks created by such a proposal; and

                  WHEREAS, should the Corporation receive any such proposals, in
addition to the Executive's regular duties, he may be called upon to assist in
the assessment of such proposals, to advise management and the Board as to
whether such proposals would be in the best interests of the Corporation and its
shareholders, and to take such other actions as the Board might determine to be
appropriate; and

                  WHEREAS, the Board also desires to encourage the continued
dedication of the Executive to the Corporation and the Bank and to promote the
stability of the Corporation's and the Bank's management by providing certain
protections for the Executive in the event that a hostile Change in Control (as
hereinafter defined) occurs with respect to the Corporation;

                  NOW, THEREFORE, to assure the Corporation and the Bank that
they will have the continued dedication of the Executive and the availability of
his advice and counsel notwithstanding the possibility, threat or occurrence of
a bid to take over control of the Corporation, and to induce the Executive to
remain in the employ of the Corporation, and for other good and valuable
consideration, the Corporation, the Bank and the Executive agree as follows:

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                  1. SERVICES DURING CERTAIN EVENTS. In the event a person or
group begins a tender or exchange offer, circulates a proxy to shareholders, or
takes other steps seeking to effect a Change of Control (as defined in Section 4
below), the Executive agrees that he will not voluntarily leave the employ of
the Corporation and will render the services contemplated in the recitals to
this Agreement until the earlier of (i) the date such person or group has
abandoned or terminated his or its efforts to effect a Change of Control, or
(ii) three (3) months after a Change of Control has occurred.

                  2. TERMINATION AFTER CHANGE OF CONTROL.

                           (a) In the event of a Termination (as defined in
         Section 4(b)below) of the Executive's employment with the Corporation
         (including the Bank) within 24 months after a Change of Control of the
         Corporation, the Corporation shall be obligated, subject to the
         limitation contained in Section 2(b) below, to pay the Executive, as
         compensation for services rendered to the Corporation and as
         consideration for the covenant not to compete set forth in Section 6,
         an amount equal to 2.99 times the Executive's base salary compensation
         (exclusive of all bonus amounts) paid in the last complete calendar
         year prior to the date of Termination. Such amount shall be payable to
         the Executive in eight (8) equal quarterly installments (subject to any
         applicable payroll or other taxes required to be withheld), over a two
         (2) year period, without interest, with the first such payment made not
         later than 30 days after the Executive's last day of employment with
         the Corporation and each succeeding payment being due on the same day
         of every third calendar month thereafter. In the event the Executive
         dies at any time during the two years following his Termination, any
         remaining unpaid installments provided for by this Section 2(a) shall
         be paid to his estate. Notwithstanding the foregoing, at the sole
         election of the Corporation, the entire amount payable to the Executive
         pursuant to this Section 2(a) may be paid in a lump sum, not later than
         the 30th day following the Executive's last day of employment with the
         Corporation.

                           (b) Notwithstanding anything in this Agreement to the
         contrary, in the event that the amount payable to the Executive
         pursuant to Section 2(a) above, when added to all other amounts paid or
         to be paid to, and the value of all property received or to be received
         by, the Executive in anticipation of or following a Change of Control,
         whether paid or received pursuant to this Agreement or otherwise (such
         other amounts and property being referred to herein as "Other Change in
         Control Payments"), would constitute an excess parachute payment within
         the meaning of Section 280G of the Internal Revenue Code of 1986, as
         amended (or any successor or renumbered section), then the amount
         payable pursuant to Section 2(a) of this Agreement or, as directed by
         the Executive, such Other Change in Control Payments shall be reduced
         to the maximum amount which, when added to such Other Change in Control
         Payments, does not constitute an excess parachute payment. For purposes
         of determining the extent to which payments pursuant to this Agreement
         and/or Other Change in Control Payments must be reduced, the value of
         the covenant not to compete set forth in Section 6 shall be valued by
         an independent certified public accounting firm retained by the
         Corporation.


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                  3. OTHER EMPLOYMENT. The Executive shall not be obligated to
seek other employment for mitigation of the amounts payable or arrangements made
under any provision of this Agreement.

                  4. DEFINITIONS. For purposes of this Agreement, the following
terms shall have the following respective meanings:

                           (a) A "CHANGE OF CONTROL" shall be deemed to have
         taken place if any of the following events occurs and the Board of
         Directors of the Corporation, as constituted prior to event occurring,
         has not expressly approved the transaction or event by at least a
         two-thirds vote of the entire Board:

                                            (i) as the result of, or in
                                    connection with any tender or exchange
                                    offer, consolidation, merger or other
                                    business combination, sale of assets or
                                    contested election or any combination of the
                                    foregoing transactions (a "Transaction"),
                                    the persons who were directors of the
                                    Corporation before the Transaction shall
                                    cease for any reason to constitute at least
                                    50% of the Board of Directors of the
                                    Corporation or any successor to the
                                    Corporation; or

                                            (ii) any "person" (as that term is
                                    used in Section 13(d) and 14(d)(2) of the
                                    Securities and Exchange Act of 1934 (the
                                    "Exchange Act") as in effect on the date
                                    hereof), including a "group" as defined in
                                    Section 13(d)(3) of the Exchange Act,
                                    becomes the beneficial owner, directly or
                                    indirectly, of shares of the Corporation
                                    having more than 50% of the total number of
                                    votes that may be cast for the election of
                                    Directors of the Corporation; or

                                            (iii) the Corporation is merged or
                                    consolidated with another corporation and as
                                    a result of the merger or consolidation less
                                    than 50% of the outstanding voting
                                    securities of the surviving or resulting
                                    corporation shall then be owned in the
                                    aggregate by the former stockholders of the
                                    Corporation, other than affiliates within
                                    the meaning of the Exchange Act or any party
                                    to the merger or consolidation; or

                                            (iv) a tender offer or exchange
                                    offer is made and consummated for the
                                    ownership of securities of the Corporation
                                    representing more than 50% of the combined
                                    voting power of the Corporation's then
                                    outstanding voting securities; or

                                             (v) the Bank transfers
                                    substantially all of its assets to another
                                    Corporation which is not a direct or
                                    indirect wholly-owned subsidiary of the
                                    Corporation.

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                           (b) "TERMINATION" shall mean (1) termination by the
         Corporation of the employment of the Executive with the Corporation
         (including the Bank) for any reason other than death, Disability (as
         defined in Section 4(d)) or Cause (as defined in Section 4(c)), or (2)
         the resignation of the Executive for either of the following events:

                                            (i) A reduction in the Executive's
                                    salary and eligibility for bonuses,
                                    incentive compensation and benefits from
                                    that in effect in last complete calendar
                                    year prior to the Change of Control, or (ii)
                                    a change in the location where the Executive
                                    is required to perform services of more than
                                    25 miles from his current residence or more
                                    than 25 miles from 24 Church Street,
                                    Canajoharie, New York; provided that prior
                                    to the Executive's resignation, he provides
                                    written notice to the Corporation of his
                                    intent to resign pursuant to this paragraph
                                    and provides the Corporation a 30 days to
                                    cure the stated condition.

                           (c) "CAUSE" shall mean the Executive's unreasonable
         neglect or refusal to perform the material duties of his position,
         fraud, misappropriation or intentional material damage to the property
         or business of the Corporation or commission of a felony.

                           (d) "DISABILITY" shall mean the Executive's absence
         from his duties with the Corporation on a full time basis for six (6)
         successive months, or for shorter periods aggregating seven (7) months
         or more in any year, as a result of the Executive's incapacity due to
         physical or mental illness, unless within 30 days after the Corporation
         gives written notice of termination following such absence the
         Executive shall have returned to the full time performance of his
         duties.

                  5. TRADE SECRETS. It is recognized that the Corporation and
the Bank have acquired and developed and will continue to acquire and develop
techniques, plans, processes, computer programs, and lists of customers and
their particular requirements which may pertain to Bank related services and
equipment, and related trade secrets, know-how, research and development, which
are proprietary and confidential in nature and are and will continue to be of
unique value to the Corporation and the Bank and its business (all hereinafter
referred to as "Confidential Information"). All Confidential Information known
or in the possession of Executive shall be kept and maintained by him as
confidential and proprietary to the Corporation and the Bank. The Executive
shall not disclose any Confidential Information at any time directly or
indirectly, in any manner to any person or firm, except to other employees of
the Corporation and/or the Bank on a "need to know" basis. Upon termination of
his employment for any reason, the Executive shall without demand therefore
deliver to the Corporation all Confidential Information in his possession. The
obligations of this Section shall survive the termination of this Agreement
indefinitely.


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                  6. SUCCESSORS. This Agreement shall be binding upon and inure
to the benefit of the Executive and his estate, and the Corporation and any
successors of the Corporation, but neither this Agreement nor any rights arising
hereunder may be assigned or pledged by the Executive.

                  7. MISCELLANEOUS. This Agreement represents the entire
agreement between the parties with respect to the subject matter of this
Agreement and specifically supersedes any and all oral or written agreements on
its subject matter previously entered into by the parties, including without
limitation the Change in Control Agreement, dated as of May 1, 1995 and March
31, 1998, between the Bank, the Corporation and the Executive.

                  8. SEVERABILITY. Any provision in this Agreement that is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective only to the extent of such prohibition or unenforceability
without invalidating or affecting the remaining provisions hereof, and any such
prohibition or unenforceability without invalidating or affecting the remaining
provisions hereof, and any such prohibition or unenforceability in any
jurisdiction shall not be invalidate or render unenforceable such provision in
any other jurisdiction.

                  9. CONTROLLING LAW. This Agreement shall in all respects be
governed by, and construed in accordance with, the laws of the State of New
York.

                  10. TERM OF AGREEMENT.

                           (a) The initial term of this Agreement shall commence
         as of January 1, 2001 and shall continue through December 31, 2001,
         unless earlier terminated as provided herein; provided, however, that
         in no case shall this Agreement terminate; (i) within 24 months after
         the occurrence of a Change of Control, or (ii) during any period of
         time when the Corporation has knowledge that any person or group (such
         terms are defined in Section 4(a)(ii) above) has taken steps reasonably
         calculated to effect a Change in Control until, in the opinion of the
         Board, such person or group has abandoned or terminated his or its
         efforts to effect a Change of Control. Any determination by the Board
         that such person or group has abandoned or terminated his or its
         efforts to effect a Change of Control shall be conclusive and binding
         as the Executive.

                           (b) Notwithstanding any provisions of this Agreement,
         this Agreement shall not confer upon the Executive the right to be
         retained in the service of the Corporation (including the Bank) nor
         limit the right of the Corporation or the Bank to discharge or
         otherwise deal with the Executive. It is the express understanding of
         the Executive, the Corporation and the Bank that the Executive's
         employment shall at all times be "at will", notwithstanding any
         provisions of this Agreement. Accordingly, the Executive or the
         Corporation and Bank may terminate the Executive's employment with the
         Bank at any time for any reason.

                           (c) This Agreement may be renewed only by the written
         action of both parties.

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                           IN WITNESS WHEREOF, the parties have executed this
         Agreement as of the date specified in the first paragraph of this
         Agreement.

                                    CNB FINANCIAL CORP.



                                    By:
                                       -----------------------------------------
                                         VanNess D. Robinson, Chair
                                         Executive Committee

                                    CENTRAL NATIONAL BANK, CANAJOHARIE



                                    By:
                                       -----------------------------------------
                                         Donald L. Brass, President

                                    EXECUTIVE:


                                       -----------------------------------------
                                         Peter J. Corso


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