Not only that, but there appear to be potential buffer overflows which involve the data pulled from the wiki page[1]. I'm not sure why asprintf wasn't used here (and in other places). The partial re-implementation of libc[2, 3] is also somewhat frightening. As are potential unchecked integer overflows when calculating a size to pass to malloc[4].
Oh dear... I'm just sight-linting so this might be wrong, but I'm certain the function executable in src/clib-install.c [1] can be easily overflown by providing a maliciously long package name or version --neither of which are validated at all [2] despite coming straight from the wiki page, as you point out. The function allocates 256-byte buffers to store a url and file name, respectively, but blindly fills them up using sprintf with non-validated user-supplied data, and without checking the resulting number of characters written, eg:
[2] As far as I can tell, the package info from the wiki is dealt with by functions in deps/clib-package.c that, despite promising names like json_object_get_string_safe, do not ever validate the provided name or version string: