Industry:DOJ Nondiscrimination on the Basis of Disability

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Submission Response
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Final version
This response is submitted on behalf of the Open Web Application Security Project (OWASP) by the OWASP Global Industry Committee. OWASP is a worldwide free and open community focused on improving the security of application software. Our mission is to make application security "visible," so that people and organizations can make informed decisions about application security risks. Everyone is free to participate in OWASP and all of our materials are available under a free and open software license. The OWASP Foundation is a U.S. recognized 501(c)(3) not-for-profit charitable organization that ensures the ongoing availability and support for our work at OWASP. OWASP has previously submitted responses to related standards and guidance:
 * BS 8878:2009 Web accessibility. Building accessible experiences for disabled people DPC
 * W3C Mobile Web Application Best Practices Working Draft and NIST documents such as NIST SP 800-37 (Rev 1), SP 800-53 (Rev 3), SP 800-122 and IR 7628.

OWASP produces guidance documents, standards and tools such as the Top Ten, Development Guide, Code Review Guide, Testing Guide, Application Security Verification Standard and the Software assurance Maturity Model. These are already referenced by organizations such as DISA, NIST, NSA and the FFIEC. Reference: OWASP Citations http://www.owasp.org/index.php/Industry:Citations

1) Should the Department adopt the WCAG 2.0s "Level AA Success Criteria" as it's standard for Web site accessibility for entities covered by Titles II and III of the ADA? Is there any reason why the Department should consider adopting another success criteria level of the WCAG 2.0? From a website security point of view, WCAG 2.0s "Level AA Success Criteria" is not inconsistent with having a secure website. Conformance levels A, AA and AAA all require additional considerations for security due to the use of:
 * input, storage and output of additional text
 * alternative forms of CATCHA
 * input, storage and output of additional files
 * third-party services
 * additional client-side scripting
 * flexible session timeouts
 * enforcing code validity

These can all be achieved using secure development practices, but the additional requirements increase complexity. There is one aspect in the more stringent "Level AAA Success Criteria" which would be difficult to achieve in a secure manner:
 * re-authentication recovery

Reference: "Can an accessible web application be secure? Assessment issues for security testers, developers and auditors", Colin Watson, OWASP AppSec Europe 2009, http://www.owasp.org/images/2/22/AppSecEU09_owasp_appsec_eu09_colin_watson_2.ppt

6) What Resources and services are available to public accommodations and public entities to make their Web sites accessible? What is the ability of covered entities to make their Web sites accessible with in-house staff? What technical assistance should the Department make available to public entities and public accommodations to assist them with complying with this rule? The W3C WAI pages on WCAG 2.0 provide ample information. In particular the "Techniques and Failures for Web Content Accessibility Guidelines 2.0" provide excellent guidance and duplication of this effort elsewhere would appear to be un-necessary. In terms of ensuring the security is maintained, we recommend OWASP's own guidance documents, standards and tools such as the Top Ten, Development Guide, Code Review Guide, Testing Guide, Application Security Verification Standard and the Software assurance Maturity Model. These are already referenced by organizations such as DISA, NIST, NSA and the FFIEC. Reference: OWASP Citations http://www.owasp.org/index.php/Industry:Citations

7) Are there distinct or specialized features used on Web sites that render compliance with accessibility requirements difficult or impossible?

When applying website accessibility standards to transactional websites. (E-commerce, financial, healthcare, educational, eGovernment, hospitality, recreational, services, transportation, legal, et alia) It is important for users to understand that these websites must comply with security standards set forth to protect customer, patient and student information. These same security standards could make it more difficult for users with disabilities to utilize transactional websites.

The following features may render compliance with accessibility requirements difficult or impossible, however they are very important tools in protecting sensitive information in a transactional website.

Session Timeout
 * One such standard is enforcing a session timeout. Session tokens that do not expire on the HTTP server can allow an attacker unlimited time to guess or brute-force a valid authenticated session token.  If a user’s cookie file is captured or brute-forced, then an attacker can use these static session tokens to gain access to that user’s web account for that site.  OWASP recommends that idle session time out for highly protected web applications are set at 5 minutes and no more than 20 minutes for low risk applications.

Passwords
 * OWASP Recommends that website security policy for passwords include the following:
 * Password change frequency
 * Enforcement of a minimum password length
 * No maximum password length limits
 * Previous passwords should not be allowed to be chosen
 * Password lock out policy
 * Password complexity requirements
 * Password lock out

Strong Authentication
 * Strong authentication (such as tokens, certificates, etc) provides a higher level of security than username and passwords. The generalized form of strong authentication is “something you know, something you hold”. Therefore, anything that requires a secret (the “something you know”) and authenticator like a token, USB fob, or certificate (the “something you hold”) is a stronger control than username and passwords (which is just “something you know”) or biometrics (“something you are”).

OWASP recommends strong authentication for certain applications:
 * for high value transactions
 * where privacy is a strong or legally compelled consideration (such as health records, government records, etc)
 * where audit trails are legally mandated and require a strong association between a person and the audit trail, such as banking applications
 * administrative access for high value or high risk systems

CAPTCHA
 * OWASP does not recommend the use of CAPTCHA. Instead OWASP recommends that Website owner provide another method to sign up or register for a website offline or via another method. Site should use a “no follow” tag. Another option is to limit privileges of a newly signed up account or similar until a positive validation has occurred.

8) Given that most websites today provide significant amounts of services and information in a dynamic, evolving setting that would be difficult, if not impossible, to replicate through alternative, accessible means, to what extent can accessible alternatives still be provided? Might viable accessible alternatives still exist for simple, non-dynamic Web sites? It is important that alternative means provide the same level of protection to the users, their data and the business systems, so that for example weaker authentication requirements in an alternative telephone service make it easier to steal a person's identity than through an online website service, or the telephone service can be used to assist exploitation of the website (e.g. enumerate usernames).

19) The Department is interested in gathering other information or data relating to the Department’s objective to provide requirements for Web accessibility under titles II and III of the ADA. Are there additional issues or information not addressed by the Department’s questions that are important for the Department to Consider? In the OWASP response to Question 1, we stated that an accessible website can be secure. It is also worth mentioning that an insecure website possibly may not be accessible because it would be possible to create web pages (responses) which do not meet the conformance requirements. A simple example would be injecting code which includes inaccessible content from a third party website, or which breaks the code validity because an extra H1 tag has been inserted.

Draft Text version 2
This response is submitted on behalf of the Open Web Application Security Project (OWASP) by the OWASP Global Industry Committee. OWASP is a worldwide free and open community focused on improving the security of application software. Our mission is to make application security "visible," so that people and organizations can make informed decisions about application security risks. Everyone is free to participate in OWASP and all of our materials are available under a free and open software license. The OWASP Foundation is a U.S. recognized 501(c)(3) not-for-profit charitable organization that ensures the ongoing availability and support for our work at OWASP. OWASP has previously submitted responses to related standards and guidance:
 * BS 8878:2009 Web accessibility. Building accessible experiences for disabled people DPC
 * W3C Mobile Web Application Best Practices Working Draft and NIST documents such as NIST SP 800-37 (Rev 1), SP 800-53 (Rev 3), SP 800-122 and IR 7628.

1) Should the Department adopt the WCAG 2.0s "Level AA Success Criteria" as it's standard for Web site accessibility for entities covered by Titles II and III of the ADA? Is there any reason why the Department should consider adopting another success criteria level of the WCAG 2.0? From a website security point of view, WCAG 2.0s "Level AA Success Criteria" is not inconsistent with having a secure website. Conformance levels A, AA and AAA all require additional considerations for security due to the use of:
 * input, storage and output of additional text
 * alternative forms of CATCHA
 * input, storage and output of additional files
 * third-party services
 * additional client-side scripting
 * flexible session timeouts
 * enforcing code validity

These can all be achieved using secure development practices, but the additional requirements increase complexity. There is one aspect in the more stringent "Level AAA Success Criteria" which would be difficult to achieve in a secure manner:
 * re-authentication recovery

Reference: "Can an accessible web application be secure? Assessment issues for security testers, developers and auditors", Colin Watson, OWASP AppSec Europe 2009, http://www.owasp.org/images/2/22/AppSecEU09_owasp_appsec_eu09_colin_watson_2.ppt

6) What Resources and services are available to public accommodations and public entities to make their Web sites accessible? What is the ability of covered entities to make their Web sites accessible with in-house staff? What technical assistance should the Department make available to public entities and public accommodations to assist them with complying with this rule? The W3C WAI pages on WCAG 2.0 provide ample information. In particular the "Techniques and Failures for Web Content Accessibility Guidelines 2.0" provide excellent guidance and duplication of this effort elsewhere would appear to be un-necessary. In terms of ensuring the security is maintained, we recommend OWASP's own guidance documents, standards and tools such as the Top Ten, Development Guide, Code Review Guide, Testing Guide, Application Security Verification Standard and the Software assurance Maturity Model. These are already referenced by organizations such as DISA, NIST, NSA and the FFIEC. Reference: OWASP Citations http://www.owasp.org/index.php/Industry:Citations

7) Are there distinct or specialized features used on Web sites that render compliance with accessibility requirements difficult or impossible? At Conformance Level AA, no.

When applying website accessibility standards to transactional websites. (E-commerce, financial, healthcare, educational) It is important for users to understand that these websites must comply with security standards set forth to protect customer, patient and student information. These same security standards could make it more difficult for users with disabilities to utilize transactional websites.

The following features may render compliance with accessibility requirements difficult or impossible, however they are very important tools in protecting sensitive information in a transactional website.

Session Timeout
 * One such standard is enforcing a session timeout. Session tokens that do not expire on the HTTP server can allow an attacker unlimited time to guess or brute-force a valid authenticated session token.  If a user’s cookie file is captured or brute-forced, then an attacker can use these static session tokens to gain access to that user’s web account for that site.  OWASP recommends that idle session time out for highly protected web applications are set at 5 minutes and no more than 20 minutes for low risk applications.

Passwords
 * OWASP Recommends that website security policy for passwords include the following:
 * Password change frequency
 * Enforcement of a minimum password length
 * No maximum password length limits
 * Previous passwords should not be allowed to be chosen
 * Password lock out policy
 * Password complexity requirements
 * Password lock out

Strong Authentication
 * Strong authentication (such as tokens, certificates, etc) provides a higher level of security than username and passwords. The generalized form of strong authentication is “something you know, something you hold”. Therefore, anything that requires a secret (the “something you know”) and authenticator like a token, USB fob, or certificate (the “something you hold”) is a stronger control than username and passwords (which is just “something you know”) or biometrics (“something you are”).

OWASP recommends strong authentication for certain applications:
 * for high value transactions
 * where privacy is a strong or legally compelled consideration (such as health records, government records, etc)
 * where audit trails are legally mandated and require a strong association between a person and the audit trail, such as banking applications
 * administrative access for high value or high risk systems

CAPTCHA
 * OWASP does not recommend the use of CAPTCHA. Instead OWASP recommends that Website owner provide another method to sign up or register for a website offline or via another method. Site should use a “no follow” tag. Another option is to limit privileges of a newly signed up account or similar until a positive validation has occurred.

8) Given that most websites today provide significant amounts of services and information in a dynamic, evolving setting that would be difficult, if not impossible, to replicate through alternative, accessible means, to what extent can accessible alternatives still be provided? Might viable accessible alternatives still exist for simple, non-dynamic Web sites? It is important that alternative means provide the same level of protection to the users, their data and the business systems, so that for example weaker authentication requirements in an alternative telephone service make it easier to steal a person's identity than through an online website service, or the telephone service can be used to assist exploitation of the website (e.g. enumerate usernames).

19) The Department is interested in gathering other information or data relating to the Department’s objective to provide requirements for Web accessibility under titles II and III of the ADA. Are there additional issues or information not addressed by the Department’s questions that are important for the Department to Consider? In the OWASP response to Question 1, we stated that an accessible website can be secure. It is also worth mentioning that an insecure website possibly may not be accessible because it would be possible to create web pages (responses) which do not meet the conformance requirements. A simple example would be injecting code which includes inaccessible content from a third party website, or which breaks the code validity because an extra H1 tag has been inserted.

CW's notes
''CW: I think the following questions posed by the DoJ are the most relevant for response by OWASP. My comments on each of those are included below.''

1.) Should the Department adopt the WCAG 2.0s "Level AA Success Criteria" as it's standard for Web site accessibility for entities covered by Titles II and III of the ADA? Is there any reason why the Department should consider adopting another success criteria level of the WCAG 2.0?


 * From a website security point of view, WCAG 2.0s "Level AA Success Criteria" is not inconsistent with having a secure website. Conformance levels A, AA and AAA all require additional considerations for security due to the use of:
 * input, storage and output of additional text
 * alternative forms of CATCHA
 * input, storage and output of additional files
 * third party services
 * additional client-side scripting
 * flexible session timeouts
 * enforcing code validity
 * These can all be achieved using secure development practices, but the additional requirements increase complexity. There is one aspect in the more stringent "Level AAA Success Criteria" which would be difficult to achieve in a secure manner:
 * re-authentication recovery
 * Reference: "Can an accessible web application be secure? Assessment issues for security testers, developers and auditors", Colin Watson, OWASP AppSec Europe 2009, http://www.owasp.org/images/2/22/AppSecEU09_owasp_appsec_eu09_colin_watson_2.ppt

6.) What Resources and services are available to public accommodations and public entities to make their Web sites accessible? What is the ability of covered entities to make their Web sites accessible with in-house staff? What technical assistance should the Department make available to public entities and public accommodations to assist them with complying with this rule?


 * The W3C WAI pages on WCAG 2.0 provide ample information. In particular the "Techniques and Failures for Web Content Accessibility Guidelines 2.0" provide excellent guidance and duplication of this effeort elsewhere would appear to be un-necessary.  In terms of ensuring the security is maintained, we recommed OWASP's own guidance documents, standards and tools such as the Top Ten, Development Guide, Code Review Guide, Testing Guide, Application Securitity Versification Standard and the Software assurance Maturity Model.  These are already referenced by organisations such as DISA, NIST, NSA and the FFIEC.
 * Reference: OWASP Citations http://www.owasp.org/index.php/Industry:Citations''

7.) Are there distinct or specialized features used on Web sites that render compliance with accessibility requirements difficult or impossible?


 * At Conformance Level AA, no.

8.) Given that most websites today provide significant amounts of services and information in a dynamic, evolving setting that would be difficult, if not impossible, to replicate through alternative, accessible means, to what extent can accessible alternatives still be provided? Might viable accessible alternatives still exist for simple, non-dynamic Web sites?


 * It is important that alternative means provide the same level of protection to the users, their data and the business systems, so that for example weaker authentication requirements in an alternative telephone service make it easier to steal a person's identity than through an online website service, or the telephone service can be used to assist exploitation of the website (e.g. enumerate usernames).

19.) The Department is interested in gathering other information or data relating to the Department’s objective to provide requirements for Web accessibility under titles II and III of the ADA. Are there additional issues or information not addressed by the Department’s questions that are important for the Department to Consider?


 * In the OWASP response to Question 1, we stated that an accessible website can be secure. It is also worth mentioning that an insecure website possibly may not be accessible because it would be possible to create web pages (responses) which are do not met the conformance requirements.  A simple example would be injecting code which includes inaccessible content from a third party website, or which breaks the code validity because an extra H1 tag has been inserted.

Some customised About OWASP text

This response is submitted on behalf of the Open Web Application Security Project (OWASP) by the OWASP Global Industry Committee. OWASP is a worldwide free and open community focused on improving the security of application software. Our mission is to make application security "visible," so that people and organizations can make informed decisions about application security risks. Everyone is free to participate in OWASP and all of our materials are available under a free and open software license. The OWASP Foundation is a U.S. recognized 501(c)(3) not-for-profit charitable organization, that ensures the ongoing availability and support for our work at OWASP.

OWASP has previously submitted responses to related standards and guidance: and NIST documents such as NIST SP 800-37 (Rev 1), SP 800-53 (Rev 3), SP 800-122 and IR 7628.
 * BS 8878:2009 Web accessibility. Building accessible experiences for disabled people DPC
 * W3C Mobile Web Application Best Practices Working Draft

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