Report incorrect group information in users
#2190
Open
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This is already documented in ogham/rust-users#44 regarding listing the groups for the current process. However, this also affects listing the supplementary groups for a particular user.
I discovered this while implementing a file server which controls access based on the underlying filesystem permissions. If the file in question was owned by the
root
group, then it would inadvertently be accessible to everyone, as they are believed to be a member of that group.There may be other applications out there doing something similar, hence I think it's important to raise this as a security issue and not just a general bug.
The boundary for the affected versions is based on this commit and this commit, where the functionality was first introduced.