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> Without hardened userland only in access controls. You can implement |
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> for example one Trusted Path Execution with LIDS, RSBAC, GRSEC or |
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> SELinux. They could try to stop crackers that gain unpriviledge access |
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> to the host (with a remote exploit for example) to execute exploits to |
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> scale priviledges. They could give you one least priviledge approach |
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> (as PaX does) and other useful things, as isolation of daemons, |
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> resources controls. And a lot of more. With TPE however, untrusted |
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> scripts (exploits) could be launched without execution rights, and |
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> even restricting the use of perl and python, you must grant your users |
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> the access to bash. |
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|
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Thank you for taking the time to explain, but I'm afraid I don't |
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understand. I'm looking for things I can implement that don't require |
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me to understand their inner workings. This is not ideal, but I only |
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have so much time to devote to sysadmin duties since I'm not a real |
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sysadmin. My server runs a hardened profile because it hasn't caused |
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any problems, but running a hardened profile on my desktops has proven |
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to be too difficult. All of my systems run a hardened kernel but the |
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only hardened feature I've enabled in the kernel is Grsecurity set to |
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medium or low depending on the system. |
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|
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Do the hardened profile and hardened kernels do me any good without |
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further configuration? |
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|
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- Grant |
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|
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>>> In terms of userland, non hardened profile doesn't protect you at all |
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>>> against buffer overflows, you are removing one important security |
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>>> layer. SSP protects you against buffer overflows in terms that the |
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>>> vulnerable application gets killed when the canary is modified before |
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>>> the execution of the arbitrary code. PIE protects you against return |
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>>> into libc attacks that doesn't need an executable stack. PaX is not |
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>>> perfect and needs them as complementary solutions. For example I think |
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>>> that RANDEXEC was removed from PaX time ago, one buffer overflow that |
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>>> uses return into libc attack could be succesfully against one |
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>>> non-hardened binary. Since skype is a network oriented software... |
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>> |
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>> In what situations is a hardened kernel useful? |
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>> |
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>> - Grant |