From Needs to Actions to Secure Apps? The Effect of Requirements and Developer Practices on App Security

Abstract

Increasingly mobile device users are being hurt by security or privacy issues with the apps they use. App developers can help prevent this; inexpensive security assurance techniques to do so are now well established, but do developers use them? And if they do so, is that reflected in more secure apps? From a survey of 335 successful app developers, we conclude that less than a quarter of such professionals have access to security experts; that less than a third use assurance techniques regularly; and that few have made more than cosmetic changes as a result of the European GDPR legislation. Reassuringly, we found that app developers tend to use more assurance techniques and make more frequent security updates when (1) they see more need for security, and (2) there is security expert or champion involvement. In a second phase we downloaded the apps corresponding to each completed survey and analyzed them for SSL issues, cryptographic API misuse and privacy leaks, finding only one fifth defect-free as far as our tools could detect. We found that having security experts or champions involved led to more cryptographic API issues, probably because of greater cryptography usage; but that measured defect counts did not relate to the need for security, nor to the use of assurance techniques. This offers two major opportunities for research: to further improve the detection of security issues in app binaries; and to support increasing the use of assurance techniques in the app developer community.