Messages in this thread | | | Date | Wed, 15 Oct 1997 11:13:23 -0400 | From | nospam-seesignature@ceddec ... | Subject | Re: [linux-security] Malicious Linux modules (fwd) |
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The way to fix these types of problems is to add some kind of digital signatures to modules and executables (and shared libs, loaders, etc, everything in the chain).
Even as root, if I don't have access to the signing program and signature information, and the object isn't signed by a recognized location (e.g. Debian or Redhat), it wouldn't allow root to do anything a normal user couldn't do - the euid would be permanently downgraded for unsigned executables. viri couldn't compromise executables. Hackers could replace some utilities with compromised versions, but the tracks would be more obvious since they would need to leave the signed versions around.
It would still require care since any system can be defeated, but making it more difficult could eliminate some attacks.
There are a few problems. DS requires crypto, and that can create export problems with the code. Crypto is big - the DS algorithm would eat another few hundred K out of the kernel.
--- reply to tzeruch - at - ceddec - dot - com ---
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