National Information Assurance Partnership
Common Criteria Evaluation and Validation Scheme
Validation Report
for the
Cisco Web Security Appliance, Version 10.5
Report Number: CCEVS-VR-10799-2017
Dated: 08/08/17
Version: 1.0
National Institute of Standards and Technology National Security Agency
Information Technology Laboratory Information Assurance Directorate
100 Bureau Drive 9800 Savage Road STE 6940
Gaithersburg, MD 20899 Fort George G. Meade, MD 20755-6940
®
TM
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ACKNOWLEDGEMENTS
Validation Team
Sheldon Durrant
Paul Bicknell
Lisa Mitchell
Linda Morrison
Common Criteria Testing Laboratory
Pascal Patin
Kevin Zhang
Acumen Security, LLC
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Table of Contents
1 Executive Summary............................................................................................................... 4
2 Identification.......................................................................................................................... 5
3 Architectural Information .................................................................................................... 6
4 Security Policy........................................................................................................................ 7
4.1 Security Audit .................................................................................................................................................7
4.2 Cryptographic Support..................................................................................................................................7
4.3 Identification and authentication..................................................................................................................8
4.4 Security Management ....................................................................................................................................8
4.5 Protection of the TSF .....................................................................................................................................9
4.6 TOE Access .....................................................................................................................................................9
4.7 Trusted path/Channels...................................................................................................................................9
5 Assumptions, Threats & Clarification of Scope ............................................................... 10
5.1 Assumptions..................................................................................................................................................10
5.2 Threats............................................................................................................... Error! Bookmark not defined.
5.3 Clarification of Scope...................................................................................................................................10
6 Documentation..................................................................................................................... 11
7 TOE Evaluated Configuration ........................................................................................... 12
7.1 Excluded Functionality ................................................................................................................................12
8 IT Product Testing............................................................................................................... 13
8.1 Developer Testing .........................................................................................................................................13
8.2 Evaluation Team Independent Testing.......................................................................................................13
9 Results of the Evaluation .................................................................................................... 14
9.1 Evaluation of Security Target .....................................................................................................................14
9.2 Evaluation of Development Documentation...............................................................................................14
9.3 Evaluation of Guidance Documents............................................................................................................14
9.4 Evaluation of Life Cycle Support Activities...............................................................................................15
9.5 Evaluation of Test Documentation and the Test Activity .........................................................................15
9.6 Vulnerability Assessment Activity ..............................................................................................................15
9.7 Summary of Evaluation Results..................................................................................................................15
10 Validator Comments & Recommendations ...................................................................... 17
11 Annexes................................................................................................................................. 18
12 Security Target .................................................................................................................... 19
13 Glossary ................................................................................................................................ 20
14 Bibliography......................................................................................................................... 21
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1 Executive Summary
This Validation Report (VR) is intended to assist the end user of this product and any security
certification Agent for that end user in determining the suitability of this Information Technology
(IT) product for their environment. End users should review the Security Target (ST), which is
where specific security claims are made, in conjunction with this VR, which describes how those
security claims were tested and evaluated and any restrictions on the evaluated configuration.
Prospective users should carefully read the Assumptions and Clarification of Scope in Section 5
and the Validator Comments in Section 10, where any restrictions on the evaluated configuration
are highlighted.
This report documents the National Information Assurance Partnership (NIAP) assessment of the
evaluation of the Cisco Web Security Appliance Target of Evaluation (TOE). It presents the
evaluation results, their justifications, and the conformance results. This VR is not an
endorsement of the TOE by any agency of the U.S. Government and no warranty of the TOE is
either expressed or implied. This VR applies only to the specific version and configuration of
the product as evaluated and documented in the ST.
The evaluation was completed by Acumen Security in June 2017. The information in this report
is largely derived from the Evaluation Technical Report (ETR) and associated test report, all
written by Acumen Security. The evaluation determined that the product is both Common
Criteria Part 2 Extended and Part 3 Conformant, and meets the assurance requirements defined in
the collaborative Protection Profile for Network Devices (NDcPP).
The Target of Evaluation (TOE) identified in this Validation Report has been evaluated at a
NIAP approved Common Criteria Testing Laboratory using the Common Methodology for IT
Security Evaluation (Version 3.1, Rev. 4) for conformance to the Common Criteria for IT
Security Evaluation (Version 3.1, Rev. 4), as interpreted by the Assurance Activities contained in
the collaborative Protection Profile for Network Devices (NDcPP). This Validation Report
applies only to the specific version of the TOE as evaluated. The evaluation has been conducted
in accordance with the provisions of the NIAP Common Criteria Evaluation and Validation
Scheme and the conclusions of the testing laboratory in the evaluation technical report are
consistent with the evidence provided.
The validation team provided guidance on technical issues and evaluation processes and
reviewed the individual work units documented in the ETR and the Assurance Activities Report
(AAR). The validation team found that the evaluation showed that the product satisfies all of the
functional requirements and assurance requirements stated in the Security Target (ST). Based on
these findings, the validation team concludes that the testing laboratory's findings are accurate,
the conclusions justified, and the conformance results are correct. The conclusions of the testing
laboratory in the evaluation technical report are consistent with the evidence produced.
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2 Identification
The CCEVS is a joint National Security Agency (NSA) and National Institute of
Standards effort to establish commercial facilities to perform trusted product evaluations.
Under this program, security evaluations are conducted by commercial testing
laboratories called Common Criteria Testing Laboratories (CCTLs). CCTLs evaluate
products against Protection Profile containing Assurance Activities, which are
interpretation of CEM work units specific to the technology described by the PP.
The NIAP Validation Body assigns Validators to monitor the CCTLs to ensure quality
and consistency across evaluations. Developers of information technology products
desiring a security evaluation contract with a CCTL and pay a fee for their product's
evaluation. Upon successful completion of the evaluation, the product is added to NIAP's
Product Compliance List.
Table 1 provides information needed to completely identify the product, including:
 The Target of Evaluation (TOE): the fully qualified identifier of the product as
evaluated.
 The Security Target (ST), describing the security features, claims, and assurances
of the product.
 The conformance result of the evaluation.
 The Protection Profile(s) to which the product is conformant.
 The organizations and individuals participating in the evaluation.
Table 1: Evaluation Identifiers
Item Identifier
Evaluation Scheme United States NIAP Common Criteria Evaluation and Validation Scheme
TOE Cisco Web Security Appliance
Protection Profile collaborative Protection Profile for Network Devices (NDcPP)
Security Target Web Security Appliance Security Target version 1.1
Evaluation Technical
Report
VID 10799 AAR version 1.7
CC Version Version 3.1, Revision 4
Conformance Result CC Part 2 Extended and CC Part 3 Conformant
Sponsor Cisco Systems, Inc.
Developer Cisco Systems, Inc.
Common Criteria
Testing Lab (CCTL)
Acumen Security
Montgomery Village, MD
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3 Architectural Information
The Cisco Web Security Appliance TOE provides comprehensive web protection services for
web traffic. It is a web protection product that monitors HTTP/HTTPS network traffic, analyzes
the monitored network traffic using various techniques, and reacts to identified threats associated
with web traffic (such as blacklisted urls and inappropriate or malicious content).
The TOE is a secure web gateway for securing and controlling web traffic. WSA is a protection
product that can block malware, and threats that may be delivered via web traffic. WSA receives
updates from the Cisco Talos Security Intelligence. Cisco Talos prevents zero-hour attacks by
continually generating new rules that feed updates to the Cisco WSA. The updates occur every 3
to 5 minutes keeping the WSA threat database updated for current web threats. WSA includes
Advanced Malware Protection (AMP) for enhanced malware protection.
Once a threat is detected through web traffic scanning, the TOE will take action based on
authorized administrator configurable filters.
The Cisco WSA is designed to serve as a secure web gateway, providing scanning of both
inbound and outbound traffic in real time for malware. All web traffic from HTML images to
Flash content is analyzed using security and context aware scanning engines.
Intelligent multi-scanning determines which scanning engine to use based on reputation and
content type, optimizing efficiency and catch rates. Traffic inspection engines analyze traffic in
real time, breaking it into functional elements and pushing those elements to the malware
engines best designed to inspect the specific type data. Specific features such as chat,
messaging, video, and audio can be allowed or blocked.
The TOE provides two management interfaces: Command Line Interface (CLI) and web-based
Graphical User Interface. The GUI contains most of the functionality to configure and monitor
the system. However, not all CLI commands are available in the GUI; some features are only
available through the CLI.
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4 Security Policy
The TOE is comprised of several security features. Each of the security features identified above
consists of several security functionalities, as identified below.
1. Security Audit
2. Cryptographic Support
3. Identification and Authentication
4. Security Management
5. Protection of the TSF
6. TOE Access
7. Trusted Path/Channels
These features are described in more detail in the subsections below. In addition, the TOE
implements all RFCs of the NDcPP v1.0 as necessary to satisfy testing/assurance measures
prescribed therein.
4.1 Security Audit
The Cisco Web Security Appliance provides extensive auditing capabilities. The TOE can audit
events related to cryptographic functionality, identification and authentication, and
administrative actions. The Cisco Web Security Appliance generates an audit record for each
auditable event. Each security relevant audit event has the date, timestamp, event description,
and subject identity. The administrator configures auditable events, performs back-up
operations, and manages audit data storage. The TOE provides the administrator with a circular
audit trail or a configurable audit trail threshold to track the storage capacity of the audit trail.
Audit logs are backed up over an encrypted channel to an external audit server.
4.2 Cryptographic Support
The TOE provides cryptography in support of other Cisco WSA security functionality. This
cryptography has been validated for conformance to the requirements of FIPS 140-2 Level 1.
The entropy source provides 256 bits of entropy used to seed the RNG. After cryptographic keys
are used, they are zeroized.
Algorithm Cert. #
AES 4561, 4680
HMAC 3013, 3096
DRBG 1509, 1583
ECDSA 1113, 1155
RSA 2488, 2553
SHA 3739, 3831
CVL 1244, 1325
The TOE provides cryptography in support of remote administrative management via SSHv2.
The cryptographic services provided by the TOE are described in Error! Reference source not
found. below.
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Cryptographic Method Use within the TOE
Secure Shell Establishment (SSH) Used to establish initial SSH session.
Transport Layer Security (TLS) Used in TLS session establishment.
AES Used to encrypt TLS session traffic.
Used to encrypt SSH session traffic.
ECDH Used to provide key exchange in SSH
RSA Signature Services Used in TLS session establishment.
Used in SSH session establishment.
X.509 certificate signing
HMAC Used for keyed hash, integrity services in TLS an SSH session
establishment.
DRBG Used for random number generation
Used in TLS session establishment.
Used in SSH session establishment.
SHA Used to provide TLS traffic integrity verification
4.3 Identification and authentication
The TOE performs user authentication for the Authorized Administrator of the TOE. The TOE
provides authentication services for administrative users wishing to connect to the TOE’s secure
CLI and GUI administrative interfaces. Prior to an administrator logging in, a login banner is
presented at both the CLI and GUI. The TOE requires Authorized Administrators to authenticate
prior to being granted access to any of the management functionality.
The TOE can be configured to require a minimum password length of 15 characters as well as
mandatory password complexity rules that includes special characters. The TOE provides
administrator authentication against a local user database. Password-based authentication can be
performed on the serial console or remote interfaces. The SSHv2 interface also supports
authentication using SSH keys. The remote GUI is protected using TLS.
4.4 Security Management
The TOE provides secure administrative services for management of general TOE configuration
and the security functionality provided by the TOE. All TOE administration occurs either
through a secure SSHv2 session or via a local console connection. The TOE provides the ability
to securely manage:
 All TOE administrative users;
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 All identification and authentication;
 All audit functionality of the TOE;
 All TOE cryptographic functionality;
 The timestamps maintained by the TOE;
 Updates to the TOE; and
 TOE configuration file storage and retrieval.
The TOE provides capabilities to manage its security functions, and controls access to those
capabilities through the use of administrative roles with varying security management
authorizations.
Administrators can create configurable login banners to be displayed at time of login, and can
also define an inactivity timeout for each admin interface to terminate sessions after a set period
of inactivity.
4.5 Protection of the TSF
The TOE protects against interference and tampering by untrusted subjects by implementing
identification, authentication, and access controls to limit configuration to Authorized
Administrators. The TOE prevents reading of cryptographic keys and passwords.
The TOE internally maintains the date and time. This date and time is used as the timestamp that
is applied to audit records generated by the TOE. Administrators can update the TOE’s clock
manually, or can optionally configure the TOE to use NTP to synchronize the TOE’s clock with
an external time source. Finally, the TOE performs testing to verify correct operation of the
appliance itself and that of the cryptographic module.
The TOE is able to verify any software updates prior to the software updates being installed on
the TOE to avoid the installation of unauthorized software.
4.6 TOE Access
The TOE is able to download software updates from the Update Server. The TOE can terminate
inactive sessions after an Authorized Administrator configurable time-period. Once a session
has been terminated the TOE requires the user to re-authenticate to establish a new session.
The TOE can also display an Authorized Administrator specified banner on the CLI and GUI
management interfaces prior to allowing any administrative access to the TOE. Administrators
are able to exit their own administrator sessions.
4.7 Trusted path/Channels
The TOE allows trusted paths to be established to itself from remote administrators over SSHv2
for remote CLI access and HTTPS for remote GUI access. The TOE can push log files to an
external syslog server using SCP over SSH.
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5 Assumptions, Threats & Clarification of Scope
5.1 Assumptions
The Security Problem Definition, including the assumptions and threats, may be found in the
collaborative Protection Profile for Network Devices [NDcPP], version 1.0, February 27, 2015.
That information has not been reproduced here and the NDcPP should be consulted if there is
interest in that material
5.2 Clarification of Scope
All evaluations (and all products) have limitations, as well as potential misconceptions that need
clarifying. This text covers some of the more important limitations and clarifications of this
evaluation. Note that:
 As with any evaluation, this evaluation only shows that the evaluated configuration meets
the security claims made, with a certain level of assurance. The level of assurance for this
evaluation is defined within the collaborative Protection Profile for Network Devices.
 Consistent with the expectations of the Protection Profile, this evaluation did not
specifically search for, nor seriously attempt to counter, vulnerabilities that were not
“obvious” or vulnerabilities to objectives not claimed in the ST. The CEM defines an
“obvious” vulnerability as one that is easily exploited with a minimum of understanding
of the TOE, technical sophistication and resources.
 The evaluation of security functionality of the product was limited to the functionality
specified in the claimed PPs. Any additional security related functional capabilities
included in the product were not covered by this evaluation.
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6 Documentation
The following documents were provided by the vendor with the TOE for evaluation:
 Cisco Web Security Appliance Security Target, version 1.1
 Cisco Web Security Appliance CC Configuration Guide, version 1.1
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7 TOE Evaluated Configuration
The TOE consists of one or more appliances and includes the Cisco AsyncOS v10.5 software.
The Cisco AsyncOS configuration determines how packets are handled to and from the TOE’s
network interfaces. In addition, the appliance configuration determines how suspected malicious
web traffic is handled.
The TOE can optionally connect to an NTP server on its internal network for time services. Also,
if the WSA is to be remotely administered, then the management station must be connected to an
internal network, SSHv2 must be used to remotely connect to the appliance. A syslog server is
also used to store audit records. If these servers are used, they must be attached to the internal
(trusted) network. The internal (trusted) network is meant to be separated effectively from
unauthorized individuals and user traffic; one that is in a controlled environment where
implementation of security policies can be enforced.
The following figure provides a visual depiction of an example TOE deployment. The TOE
boundary is surrounded with a hashed red line.
7.1 Excluded Functionality
The following functionality is excluded from the evaluated configuration.
Table 1 Excluded Functionality
Excluded Functionality Exclusion Rationale
Non-FIPS 140-2 mode of operation This mode of operation includes non-FIPS allowed
operations.
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8 IT Product Testing
This section describes the testing efforts of the developer and the evaluation team. It is derived
from information contained in Evaluation Test Report for Cisco Web Security Appliance, which
is not publically available. The Assurance Activities Report provides an overview of testing and
the prescribed assurance activities.
8.1 Developer Testing
No evidence of developer testing is required in the Assurance Activities for this product.
8.2 Evaluation Team Independent Testing
The evaluation team verified the product according the vendor-provided guidance documentation
and ran the tests specified in the collaborative Protection Profile for Network Devices (NDcPP).
The Independent Testing activity is documented in the Assurance Activities Report, which is
publically available, and is not duplicated here.
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9 Results of the Evaluation
The results of the assurance requirements are generally described in this section and are
presented in detail in the proprietary documents: the Detailed Test Report (DTR) and the
Evaluation Technical Report (ETR). The reader of this document can assume that activities and
work units received a passing verdict.
A verdict for an assurance component is determined by the resulting verdicts assigned to the
corresponding evaluator action elements. The evaluation was conducted based upon CC version
3.1 rev 4 and CEM version 3.1 rev 4. The evaluation determined the Cisco Web Security
Appliance to be Part 2 extended, and meets the SARs contained in the PP. Additionally the
evaluator performed the Assurance Activities specified in the NDPP.
9.1 Evaluation of Security Target
The evaluation team applied each ASE CEM work unit. The ST evaluation ensured the ST
contains a description of the environment in terms of policies and assumptions, a statement of
security requirements claimed to be met by the Cisco Web Security Appliance that are consistent
with the Common Criteria, and product security function descriptions that support the
requirements. Additionally the evaluator performed an assessment of the Assurance Activities
specified in the collaborative Protection Profile for Network Devices (NDcPP).
The validator reviewed the work of the evaluation team, and found that sufficient evidence and
justification was provided by the evaluation team to confirm that the evaluation was conducted in
accordance with the requirements of the CEM, and that the conclusion reached by the evaluation
team was justified.
9.2 Evaluation of Development Documentation
The evaluation team applied each EAL 1 ADV CEM work unit. The evaluation team assessed
the design documentation and found it adequate to aid in understanding how the TSF provides
the security functions. The design documentation consists of a functional specification contained
in the Security Target's TOE Summary Specification. Additionally the evaluator performed the
Assurance Activities specified in the collaborative Protection Profile for Network Devices
(NDcPP) related to the examination of the information contained in the TOE Summary
Specification.
The validator reviewed the work of the evaluation team, and found that sufficient evidence and
justification was provided by the evaluation team to confirm that the evaluation was conducted
in accordance with the Assurance Activities, and that the conclusion reached by the evaluation
team was justified.
9.3 Evaluation of Guidance Documents
The evaluation team applied each EAL 1 AGD CEM work unit. The evaluation team ensured the
adequacy of the user guidance in describing how to use the operational TOE. Additionally, the
evaluation team ensured the adequacy of the administrator guidance in describing how to
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securely administer the TOE. The guides were assessed during the design and testing phases of
the evaluation to ensure they were complete. Additionally the evaluator performed the Assurance
Activities specified in the collaborative Protection Profile for Network Devices (NDcPP) related
to the examination of the information contained in the operational guidance documents.
The validator reviewed the work of the evaluation team, and found that sufficient evidence and
justification was provided by the evaluation team to confirm that the evaluation was
conducted in accordance with the Assurance Activities, and that the conclusion reached by
the evaluation team was justified.
9.4 Evaluation of Life Cycle Support Activities
The evaluation team applied each EAL 1 ALC CEM work unit. The evaluation team found
that the TOE was identified.
The validator reviewed the work of the evaluation team, and found that sufficient evidence and
justification was provided by the evaluation team to confirm that the evaluation was conducted in
accordance with the requirements of the CEM, and that the conclusion reached by the evaluation
team was justified.
9.5 Evaluation of Test Documentation and the Test Activity
The evaluation team applied each EAL 1 ATE CEM work unit. The evaluation team ran the set
of tests specified by the Assurance Activities in the collaborative Protection Profile for Network
Devices (NDcPP) and recorded the results in a Test Report, summarized in the Evaluation
Technical Report and Assurance Activities Report.
The validator reviewed the work of the evaluation team, and found that sufficient evidence was
provided by the evaluation team to show that the evaluation activities addressed the test activities
in the collaborative Protection Profile for Network Devices (NDcPP), and that the conclusion
reached by the evaluation team was justified.
9.6 Vulnerability Assessment Activity
The evaluation team applied each EAL 1 AVA CEM work unit. The evaluation team performed
a public search for vulnerabilities, performed vulnerability testing and did not discover any
issues with the TOE.
The validator reviewed the work of the evaluation team, and found that sufficient evidence and
justification was provided by the evaluation team to confirm that the evaluation addressed the
vulnerability analysis Assurance Activities in the collaborative Protection Profile for Network
Devices (NDcPP), and that the conclusion reached by the evaluation team was justified.
9.7 Summary of Evaluation Results
The evaluation team's assessment of the evaluation evidence demonstrates that the claims in
the ST are met. Additionally, the evaluation team's test activities also demonstrated the
accuracy of the claims in the ST.
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The validation team's assessment of the evidence provided by the evaluation team is that it
demonstrates that the evaluation team performed the Assurance Activities in the collaborative
Protection Profile for Network Devices (NDcPP), and correctly verified that the product meets
the claims in the ST.
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10 Validator Comments & Recommendations
The validators have no further comments about the evaluation results.
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11 Annexes
Not applicable.
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12 Security Target
Web Security Appliance Security Target version 1.1
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13 Glossary
The following definitions are used throughout this document:
 Common Criteria Testing Laboratory (CCTL). An IT security evaluation facility
accredited by the National Voluntary Laboratory Accreditation Program (NVLAP) and
approved by the CCEVS Validation Body to conduct Common Criteria-based
evaluations.
 Conformance. The ability to demonstrate in an unambiguous way that a given
implementation is correct with respect to the formal model.
 Evaluation. The assessment of an IT product against the Common Criteria using the
Common Criteria Evaluation Methodology to determine whether or not the claims made
are justified; or the assessment of a protection profile against the Common Criteria using
the Common Evaluation Methodology to determine if the Profile is complete, consistent,
technically sound and hence suitable for use as a statement of requirements for one or
more TOEs that may be evaluated.
 Evaluation Evidence. Any tangible resource (information) required from the sponsor or
developer by the evaluator to perform one or more evaluation activities.
 Feature. Part of a product that is either included with the product or can be ordered
separately.
 Target of Evaluation (TOE). A group of IT products configured as an IT system, or an
IT product, and associated documentation that is the subject of a security evaluation
under the CC.
 Validation. The process carried out by the CCEVS Validation Body leading to the issue
of a Common Criteria certificate.
 Validation Body. A governmental organization responsible for carrying out validation
and for overseeing the day-to-day operation of the NIAP Common Criteria Evaluation
and Validation Scheme.
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14 Bibliography
The Validation Team used the following documents to produce this Validation Report:
1. Common Criteria for Information Technology Security Evaluation - Part 1: Introduction
and general model, Version 3.1 Revision 4.
2. Common Criteria for Information Technology Security Evaluation - Part 2: Security
functional requirements, Version 3.1 Revision 4.
3. Common Criteria for Information Technology Security Evaluation - Part 3: Security
assurance requirements, Version 3.1 Revision 4.
4. Common Evaluation Methodology for Information Technology Security Evaluation,
Version 3.1 Revision 4.