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Version 1.2 of the Application PP

On October 25 version 1.1 of the Application Software Protection Profile (PP_APP) will sunset. It is being replaced with PP_APP version 1.2.

Like its predecessor PP_APP 1.2 is aimed at mobile, server and desktop application software. It is meant to be used in conjunction with Extended Packages (EPs) for more specialized applications. EPs that currently exist for this PP include the Redaction Tools EP, the SSH EP and the VoIP EP.

The changes to this version of the PP_APP are relatively modest. It has the same TOE boundary as previous versions, addresses the same use cases and includes the same threats, objectives and assumptions.

The mandatory cryptographic support (FCS) and security management (FMT) requirements have not been changed in this version of the PP. In the User Data Protection (FDP) requirements FDP_DEC_EXT.1.3 through 1.5 have been removed. What used to be FDP_DEC_EXT.1.4 is now a separate SFR named FDP_NET_EXT.1.1. FDP_DEC_EXT.1.3 and 1.5 which cover justification for accessing resources and protection of Personally Identifiable Information (PII) have been taken out completely. In addition, there have been some minor changes to the Android assurance activities for FDP_DEC_EXT.1.1 and 1.2. As in the previous version PP_APP 1.2 does not have any mandatory identification and authentication (FIA) SFRs.

To cover the PII related requirement that was removed from FDP this new PP adds a privacy related SFR named FPR_ANO_EXT.1. Even though the name and family of the SFR has changed the wording of the requirement and the related assurance activity have remained the same.

Mandatory requirements for the protection of the (FPT) have also remained the same in this PP update. In the trusted path/channel (FTP) requirements it is now permissible to use SSH to protect data in transit if the SSH EP is used as well. This is covered in FTP_DIT_EXT.1. The assurance activities for that SFR now also include more specific instructions for TOEs running on iOS and Android.

In its optional requirements the updated PP now includes an SFR for the generation of symmetric cryptographic keys. The purpose of this SFR is to support the generation of keys along a key chain. At this time the assurance activities for this SFR are purely documentation based, although it also relies on FCS_RBG_EXT.1. The other minor change to optional requirements has been to rename FCS_TLSC_EXT.1.4 which is the SFR for TLS mutual authentication to FCS_TLSC_EXT.2.1.

In the PP’s selection based requirements FCS_RBG_EXT.2.1 has been changed to remove support for FIPS 140-2 X9.31 random bit generation. The previous version of the PP had warned that these DRNGs would be disallowed after 2015 so this change should come as no surprise to developers.

FCS_COP.1.1(1) has been changed to make 256-bit keys mandatory while 128-bit keys are optional which is the opposite of the previous PP version. This was another change that old PP had said would be made in 2015. FCS_COP.1.1(2) has also removed SHA-1 as a mandatory hashing algorithm and made it an optional selection instead. In the TLS client requirements FCS_TLSC_EXT.1.5 has been renamed FCS_TLSC_EXT.4.1 even though the wording and assurance activities have remained the same.

One new capability that has been added to PP_APP 1.2 is TLS Server. The requirement says that it depends on a selection in FTP_DIT_EXT.1 however FTP_DIT contains no selection that requires FCS_TLSS. This was presumably an oversight on the part of the PP authors and will likely soon be corrected by a NIAP technical decision.

As we’ve shown the newest version of the PP_APP contains a number of changes but most of them are administrative in nature. The updates that have been made to bring it up to current cryptography standards were all described in the previous PP version. The only new capabilities that are covered are for SSH and TLS server, and those are both optional. Developers who have created products for previous versions of the PP_APP should have little difficulty meeting the standards of the updated protection profile.

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