  Third-party library reuse has become common practice in contemporary software
development, as it includes several benefits for developers. Library
dependencies are constantly evolving, with newly added features and patches
that fix bugs in older versions. To take full advantage of third-party reuse,
developers should always keep up to date with the latest versions of their
library dependencies. In this paper, we investigate the extent of which
developers update their library dependencies. Specifically, we conducted an
empirical study on library migration that covers over 4,600 GitHub software
projects and 2,700 library dependencies. Results show that although many of
these systems rely heavily on dependencies, 81.5% of the studied systems still
keep their outdated dependencies. In the case of updating a vulnerable
dependency, the study reveals that affected developers are not likely to
respond to a security advisory. Surveying these developers, we find that 69% of
the interviewees claim that they were unaware of their vulnerable dependencies.
Furthermore, developers are not likely to prioritize library updates, citing it
as extra effort and added responsibility. This study concludes that even though
third-party reuse is commonplace, the practice of updating a dependency is not
as common for many developers.
