libgit2 is a portable C implementation of the Git core methods provided as a linkable library with a solid API, allowing to build Git functionality into your application. Prior to 1.8.6 and 1.9.5, libgit2 does not reject traversal components in a submodule path loaded from .gitmodules. The affected src/libgit2/submodule.c paths include git_submodule_lookup and git_submodule_add_setup. A crafted repository can specify a path such as ../escape-target, and applications that initialize the submodule can create directories outside the repository working tree. This issue is fixed in versions 1.8.6 and 1.9.5.
References
- https://github.com/libgit2/libgit2/commit/419637d3587396f5d139d6d88480eab3cd81e7a1
- https://github.com/libgit2/libgit2/commit/467c2d95ed663df722f83a5960edf568514b128c
- https://github.com/libgit2/libgit2/commit/ec7371da9f359cd8293e9108e7a0b1c1b61b67c4
- https://github.com/libgit2/libgit2/releases/tag/v1.8.6
- https://github.com/libgit2/libgit2/releases/tag/v1.9.5
- https://github.com/libgit2/libgit2/security/advisories/GHSA-cw77-j82w-mchm