Exhibit 99.1


Sourcefire Acquires ClamAV Open Source Network Anti-Virus Project

  Acquisition Expands Company's Open Source Portfolio and Commercial
                 Enterprise Threat Management Strategy


    COLUMBIA, Md.--(BUSINESS WIRE)--Aug. 17, 2007--Open source
innovator and SNORT (R) creator, Sourcefire, Inc. (Nasdaq:FIRE), today
announced that it has acquired ClamAV(TM), a leading open source
gateway anti-virus and anti-malware project. Sourcefire's first
acquisition since its Initial Public Offering in March 2007, ClamAV
will broaden the company's open source footprint while providing the
technology foundation for new products and services that will extend
the company's Enterprise Threat Management network security portfolio.

    With nearly 1 million unique IP addresses downloading ClamAV
malware updates daily across more than 120 mirrors in 38 countries,
ClamAV is one of the most broadly adopted open source security
projects worldwide. ClamAV has also been recognized as comparable in
quality and coverage to leading commercial anti-virus solutions. Most
recently, at LinuxWorld this year, ClamAV was one of only three
anti-virus technologies to provide a 100% detection rate in their live
'Fight Club' test featuring live submissions from the show audience.

    Under terms of the transaction, Sourcefire has acquired the ClamAV
project and related trademarks, as well as the copyrights held by the
five principal members of the ClamAV team including project founder
Tomasz Kojm. Sourcefire will also assume control of the open source
ClamAV project including the ClamAV.org domain, web site and web site
content and the ClamAV Sourceforge project page. In addition, the
ClamAV team will remain dedicated to the project as Sourcefire
employees, continuing their management of the project on a day-to-day
basis.

    In accounting for the transaction, Sourcefire anticipates a
one-time charge in the third quarter of 2007 of between $0.09 and
$0.12 per share for the immediate write-off of in-process research and
development, which will be classified as an extraordinary item.
Details of the transaction consideration are not being disclosed.

    "This acquisition gives Sourcefire the ability to bring together
two of the security industry's most widely adopted open source
projects; Snort and ClamAV. This will not only broaden our reach, but
will also allow us to extend our product family into a number of
intriguing new markets," said Martin Roesch, Founder and CTO of
Sourcefire and Creator of Snort. "The success of the ClamAV project is
a direct reflection of the talent and dedication of the founding team
and the project community. Sourcefire will continue to invest in the
ClamAV technology, much as we have with Snort and Snort.org.
Sourcefire pioneered the business of balancing commercial solutions
with open source innovation, and we intend to apply those same Snort
sensibilities to the ClamAV project."

    ClamAV has been adopted by network security solution and service
providers worldwide and is currently integrated within leading
enterprise solutions, including Unified Threat Management Systems
(UTM), Secure Web Gateways and Secure Mail Gateways, to identify
deeply embedded threats such as viruses, trojans, spyware, and other
forms of malware.

    "We are very excited to join Sourcefire and we believe that this
combination will allow us to deliver increased value to the open
source community, as well as Sourcefire's commercial customers," said
Tomasz Kojm, ClamAV Project Founder. "Sourcefire is a well respected
company in the open source arena, and they really understand how to
balance open source community investment with the commercial needs of
their customers. This is an exciting development for me, as the
project founder, and I look forward to the future growth of the ClamAV
technology and community."

    Conference Call and Webcast

    On Friday, August 17, 2007 at 11:00 a.m. Eastern Time, Sourcefire
will host a conference call to review this announcement. A listen-only
web cast of the session will be available at
http://investor.sourcefire.com. Those wishing to participate in the
live session should use the following numbers to dial in:

- -0-
*T
Calling from the United States or Canada: 866-831-6270
Calling from other countries: 617-213-8858
Pass code: 19013275
*T

    An online replay will be available at
http://investor.sourcefire.com following the completion of the live
call and will remain available for at least 90 days.

    About Sourcefire

    Sourcefire, Inc. (Nasdaq:FIRE), Snort creator and open source
innovator, is a world leader in Enterprise Threat Management (ETM)
solutions. Sourcefire is transforming the way Global 2000
organizations and government agencies manage and minimize network
security risks with its 3D Approach - Discover, Determine, Defend - to
securing real networks. The Sourcefire 3D(TM) System is the first to
unify IPS, NBA, NAC and Vulnerability Assessment technologies under
the same management console. This ETM approach equips customers with
an efficient and effective layered security defense - protecting
network assets before, during and after an attack. Through the years,
Sourcefire has been consistently recognized for its innovation and
industry leadership by customers, media and industry analysts alike -
with more than 30 awards and accolades. Recently, Sourcefire was
positioned in the Leaders Quadrant of Gartner's "Magic Quadrant for
Network Intrusion Prevention System Appliances 2H06" report, and the
Sourcefire 3D System was named "Best Security Solution" at the 2006 SC
Magazine Awards. Today, the names Sourcefire and founder Martin Roesch
have grown synonymous with innovation and network security
intelligence. For more information about Sourcefire, please visit
http://www.sourcefire.com.

    SOURCEFIRE(R), SNORT(R), the Sourcefire logo, the Snort and Pig
logo, SECURITY FOR THE REAL WORLD(TM), SOURCEFIRE DEFENSE CENTER(TM),
SOURCEFIRE 3D(TM), RNA(TM), DAEMONLOGGER(TM) and certain other
trademarks and logos are trademarks or registered trademarks of
Sourcefire, Inc. in the United States and other countries.

    Cautionary Language Concerning Forward-Looking Statements

    The statements contained in this release that are not historical
facts are "forward-looking statements" (as such term is defined in the
Private Securities Litigation Reform Act of 1995) that involve risks
and uncertainties. These statements, which can be identified by words
or expressions such as "will," "believe," "expect," "anticipate,"
"intend" and similar expressions, include our expectations regarding
Sourcefire's offering of ClamAV as an open source solution, its
integration of ClamAV into Sourcefire's commercial ETM offerings, the
future roles and performance of the ClamAV personnel as Sourcefire
employees, the amount of the accounting charge expected to be incurred
in connection with the write-off of in-process research and
development as a result of the transaction and Sourcefire's intention
to invest in the ClamAV technology. Actual results, performance,
and/or achievements of Sourcefire, Inc. may differ materially from the
future results, performance, and/or achievements expressed or implied
by these forward-looking statements. Management cautions the reader
that these forward-looking statements are only predictions and are
subject to a number of both known and unknown risks and uncertainties,
including Sourcefire's ability to integrate ClamAV into its existing
ETM commercial offerings, the continued employment by Sourcefire of
the ClamAV personnel, the final allocation of the purchase price of
the transaction, Sourcefire's future budgetary decisions, and other
factors, including without limitation, those risks and uncertainties
described in the "Risk Factors" section of Sourcefire's Form 10-Q for
the quarter ended June 30, 2007 and other reports filed from time to
time by Sourcefire with the Securities and Exchange Commission.
Sourcefire undertakes no obligation to update any forward-looking
statements.


    CONTACT: Sourcefire, Inc.
             Investor Contact:
             Tania Almond
             Investor Relations Officer
             410-423-1919
             tania.almond@sourcefire.com
             or
             Media Contact:
             Welz & Weisel Communications
             Tony Welz
             Principal
             703-218-3555 x226
             tony@w2comm.com