Re: [Re: Amanda multiple vendor local root compromises]

From: Robert Watson (robertat_private)
Date: Tue Nov 02 1999 - 10:43:00 PST

  • Next message: Mariusz Woloszyn: "Re: "Function pointer" attacks."

    On Mon, 1 Nov 1999, Peter Walker wrote:
    
    > I think it is fair to say that there is a problem with the amanda package
    > as it is shipped on the FreeBSD 3.3 CD, rather than with the amanda backup
    > system itself. It would be interesting to find out if any other "standard"
    > os distributions have similar problems.
    >
    > Personally I would be very wary of entrusting the security of any of our
    > systems to somebody else's packaging of a software package that by its
    > nature requires unrestricted read access to all of my disks.
    
    On the other hand, if you don't trust your OS with the contents of your
    disk, you're probably not going to install the OS.  There is an equally
    strong argument that you should trust your OS vendor to adapt generally
    available packages for the local OS environment--often software developers
    write their software with a particular security architecture in mind (say,
    Linux or Solaris) which isn't quite the same as the local system (say,
    OpenBSD or FreeBSD).  Installing SSH without vendor patches can often be
    a problem, as pointed out with the recent chflags-related bugs (where the
    SSH authors assumed that certain operations would always succeed).  OS
    adaptation places some of the responsibility for security verification on
    the OS vendor or package developer, which seems appropriate, given that
    the OS vendor probably understands the OS best.
    
    That said, it's probably also best if the OS vendor submits patches back
    to the software developer, and that the software developer incorporates
    the patches.  There have been a number of cases where the FreeBSD
    community has failed to submit patches on software back to the developer,
    so the developer never knew that these changes were required on FreeBSD.
    There have also been numerous cases where the changes *have* been
    submitted back, but have been ignored by the vendor.  I don't know that
    Amanda falls into either case, but it is something to consider when
    judging the merit of even having a OS-specific package system :-).
    
    It should also be pointed out that the symlink bug described in the
    original post seems to be a bug in Amanda that is not platform-specific --
    I haven't seen any further comment on that, only on the package
    installation.  Has anyone verified that the amanda.debug file is created
    in such a way that a) it has a predictable name, and b) it follows
    symlinks?  Really, it should probably go in /var/run (or equiv directory
    on whatever OS), should be created using O_CREAT and O_EXCL, or should be
    created using mktemp.  Probably the first option is best.
    
      Robert N M Watson
    
    robertat_private              http://www.watson.org/~robert/
    PGP key fingerprint: AF B5 5F FF A6 4A 79 37  ED 5F 55 E9 58 04 6A B1
    TIS Labs at Network Associates, Safeport Network Services
    



    This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 15:09:29 PDT